Systems and methods for switching zero charge callers

ABSTRACT

Asynchronous and/or synchronous zero charge telephony protocol systems and methods may include an asynchronous signaling switch and/or a call duration time quota from a synchronous charging onset to place and complete a call. A first device call request is received with a second device mobile address. The asynchronous systems include instructions to automatically modify the mobile address with a routing prefix when the first device has insufficient balance or independent of balance, route to the asynchronous signaling switch based on an associated modified address trunk path, revert the modified call signal at the asynchronous signaling switch to the call signal, and deliver and automatically disconnect the call immediately when the call is completed. The synchronous systems include instructions to automatically set the call duration time quota upon insufficient balance, and deliver and automatically disconnect the call from the second user mobile device when the call is completed and the call duration time quota is exceeded.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation-in-part of U.S. patentapplication Ser. No. 16/938,236, filed Jul. 24, 2020, the entirety ofwhich is incorporated by reference herein.

TECHNICAL FIELD

The present specification generally relates to intelligent network (IN)switching systems and, more specifically, to systems and methods forswitching and servicing callers based on insufficient account balance orindependent of balance. A portion of the disclosure of this patentdocument contains material which is subject to copyright protection. Thecopyright owner has no objection to the facsimile reproduction by anyoneof the patent document or the patent disclosure, as it appears in thePatent and Trademark Office patent file or records, but otherwisereserves all copyright rights whatsoever.

BACKGROUND

Users of many of the prepaid mobile calling systems of today may findthemselves without any credit or with insufficient credit to place acall. Users may have insufficient resources for telecommunications topurchase credit or fund an account balance sufficient to place a call.Thus, the cost of access to such mobile calling systems is prohibitiveto many users. A need exists for alternative mobile calling systems toprovide access to such users.

SUMMARY

In one embodiment, a zero charge telephony protocol system includes oneor more processors, a non-transitory memory communicatively coupled tothe one or more processors, and machine readable instructions. Themachine readable instructions are stored in the non-transitory memoryand cause the system to perform at least the following when executed bythe one or more processors: receive, from a first user mobile deviceassociated with a first user account, a call signal comprising a requestto place and complete a call to a mobile address of a second user mobiledevice; automatically modify the mobile address with a routing prefix togenerate a modified call signal comprising a modified address, includingthe routing prefix, when the first user account has insufficient balanceto complete the call or is independent of balance; route to anasynchronous signaling switch based on a trunk communication pathassociated with the modified address; revert the modified call signal atthe asynchronous signaling switch to the call signal; deliver the callsignal from the asynchronous signaling switch to the second user mobiledevice to complete the call; and automatically disconnect the call fromthe second user mobile device immediately upon receipt of the callsignal by the second user mobile device.

In another embodiment, a method of implementing a zero charge telephonyprotocol includes receiving, from a first user mobile device associatedwith a first user account, a call signal comprising a request to placeand complete a call to a mobile address of a second user mobile device,and automatically modifying the mobile address with a routing prefix togenerate a modified call signal comprising a modified address includingthe routing prefix when the first user account has insufficient balanceto complete the call or is independent of balance. The method mayfurther include routing to an asynchronous signaling switch based on atrunk communication path associated with the modified address, revertingthe modified call signal at the asynchronous signaling switch to thecall signal, delivering the call signal from the asynchronous signalingswitch to the second user mobile device to complete the call, andautomatically disconnecting the call from the second user mobile deviceimmediately upon receipt of the call signal by the second user mobiledevice.

In one other embodiment, a zero charge telephony protocol systemincludes one or more processors, a non-transitory memory communicativelycoupled to the one or more processors, machine readable instructionsstored in the non-transitory memory that cause the system to perform atleast the following when executed by the one or more processors:receive, from a first user mobile device associated with a first useraccount, a call signal comprising a request to place and complete a callto a mobile address of a second user mobile device; automatically set acall duration time quota upon a synchronous charging onset when thefirst user account has insufficient balance to complete the call;deliver the call signal to the second user mobile device to complete thecall; and automatically disconnect the call from the second user mobiledevice when the call duration time quota is exceeded after thesynchronous charging onset.

These and additional features provided below will be more fullyunderstood in view of the following detailed description, in combinationwith the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments set forth in the drawings are illustrative and exemplaryin nature and not intended to limit the disclosure. The followingdetailed description of the illustrative embodiments can be understoodwhen read in combination with the following drawings, where likestructure is indicated with like reference numerals, and in which:

FIG. 1A schematically depicts a flowchart of a method for a dual zerocharge sub scriber identification module (SIM) card system and abalance-dependent (e.g., prepaid) SIM card associated with a first usermobile device, according to one or more embodiments shown and describedherein;

FIG. 1B schematically depicts a flowchart of a method for single zerocharge SIM card system including a balance-independent SIM cardassociated with a first user mobile device, according to one or moreembodiments shown and described herein;

FIG. 1C schematically depicts a routing and switching scheme for thezero charge SIM card system of FIG. 1A or the balance-independent SIMcard of FIG. 1B, according to one or more embodiments shown anddescribed herein;

FIG. 2 schematically depicts a flowchart of a method for continuing themethod of FIG. 1A or FIG. 1B upon using the scheme of FIG. 1C, accordingto one or more embodiments shown and described herein;

FIG. 3A schematically depicts a control scheme illustrating a sequentialstep ladder structure utilizing the methods of FIG. 1A and FIG. 2,according to one or more embodiments shown and described herein;

FIG. 3B schematically depicts a control scheme illustrating a sequentialstep ladder structure utilizing the methods of FIG. 1B and FIG. 2,according to one or more embodiments shown and described herein;

FIG. 4A schematically depicts a control scheme for an originating flashhook protocol for the control schemes for FIG. 3A or 3B, according toone or more embodiments shown and described herein;

FIG. 4B schematically depicts a control scheme for a terminating flashhook protocol for the control schemes for FIG. 3A or 3B, according toone or more embodiments shown and described herein;

FIG. 5 schematically depicts a parallel architecture utilizing thebalance-dependent SIM card and the balance-independent SIM card of thesystems of FIG. 1A and FIG. 1B or of the zero charge SIM card system ofFIG. 1A, according to one or more embodiments shown and describedherein;

FIG. 6A schematically depicts a unified logic model of thebalance-dependent and balance-independent service key logic for themethods of FIGS. 1A and 2, according to one or more embodiments shownand described herein;

FIG. 6B schematically depicts a parallel logic model ofbalance-dependent and zero charge SIM card system utilizing service keylogics for the methods of FIG. 1A or 1B and FIG. 2, according to one ormore embodiments shown and described herein;

FIG. 6C schematically depicts a native logic model of a prepaid zerocharge service key logic for a quota based synchronous zero cost scheme,according to one or more embodiments shown and described herein;

FIG. 7 schematically depicts an asymmetrical zero charge, andbalance-independent SIM card CLI provision, according to one or moreembodiments shown and described herein;

FIG. 8 schematically depicts a system for implementing computer andsoftware based methods for the zero charge SIM card protocols, accordingto one or more embodiments shown and described herein;

FIG. 9A schematically depicts a low frequency alternating connectswitching algorithm, according to one or more embodiments shown anddescribed herein;

FIG. 9B schematically depicts a high frequency alternating connectswitching algorithm, according to one or more embodiments shown anddescribed herein;

FIG. 10 schematically depicts a flowchart of a method for a callerdriven connect switching flow, according to one or more embodimentsshown and described herein; and

FIG. 11 schematically depicts a flowchart of a method for mid calladvertisement sponsored free call service, according to one or moreembodiments shown and described herein.

DETAILED DESCRIPTION

Embodiments of the present disclosure are directed to technology forcellular call access and related mobile calling systems. Such technologymay be configured to interact with a smart mobile device of a user, forinstance. The term “interact” or “interaction” as referenced hereindescribe an electronic communication including a transmission andreception of electronic data signals directly or indirectly between atleast two electronic devices, such as through wired or wirelesselectronic communication networks. Various autonomous navigation methodsand systems will be described in more detail herein with specificreference to the corresponding drawings.

As described below, the mobile calling systems and methods provide anasynchronous calling scheme between a first user mobile device 820 of afirst user, a second user mobile device 824 of a second user (as shownin FIGS. 2, and 8), and a switching node as a switch component 812 (asshown in FIG. 8) such that the first user mobile device is not chargedfor placing and momentarily completing a call to the second user mobiledevice through use of a customized connection logic. An embodiment ofthe switch component 812 is shown as “Star Switch” based on a starsymbol routing prefix in FIGS. 1A, 1B, and 2, and will be described ingreater detail below. Reference to “Star Switch” may be similarlyapplied to other embodiments of the switch component 812 based on arouting prefix other than a star symbol routing prefix.

Further, a caller may place and complete the call when the caller hasinsufficient account balance, e.g. associated with a SIM card, which isSIM card is associated with a user mobile device. In embodiments of theasynchronous calling scheme, as will be described in greater detailbelow with respect to at least FIGS. 1A-6A and 8, a call from the firstuser mobile device by the first user to the second user mobile device ofthe second user is indirectly placed by being first sent by the firstuser mobile device to the switching node using the customized connectionlogic, disconnected by the switching node from the first user mobiledevice, and sent from the switching node to the second user mobiledevice such that the first user mobile device is not directly connectedto the second user mobile device, and the first user mobile device isnot charged for the call. In embodiments of synchronous calling schemes,as described below with respect to at least FIGS. 6C and 8, a callduration time quota may be applied at charging onset to the first usermobile device to automatically and immediately disconnect the call atthe second user mobile device, e.g., prior to incurring a charge. Thus,through the customized connection logic of asynchronous calling schemesand/or as synchronous calling schemes, users may place and completecalls without an account balance, or with insufficient balance.

In many current mobile calling systems, a prepaid or postpaidsynchronous mobile calling system is utilized in which a positivebalance is required to place and complete a call. As described herein, aplaced call is indicative of initiating a call signal associated with arequest to dial a mobile address of another user device, a completedcall occurs upon receipt of the call signal by another user device atthe mobile address (e.g., ringing at the other user device), and ananswered call is associated with an answering of the completed call(e.g., pickup and speech). With balance-dependent prepaid mobile callingsystems, a first user with limited funds may attempt to place (e.g.,dial and send) a call through a first user mobile device to a seconduser mobile device of a second user, which rings as a completed call(which ringing does not incur a charge), and then disconnect prior toanswer of the ringing that would incur a charge. Such a beeping orflashing method is used to signal the second user to call back the firstuser without the first user incurring a charge. Thus, the second user isaware of the missed call, and calls the first user back to incur thecall charge and effectively reverse charges.

However, while ringing is free, many prepaid mobile calling systemsrequire a sufficient paid (e.g., debit) balance to initiate and progressthe call to ringing, and thus to place and complete the call. Users mayfind themselves with insufficient credit (e.g., balance) after depletinga prepaid account for airtime and cellular access, and consequently areprevented from even placing a call based on the insufficient credit.Further, many users do not have financial resources fortelecommunications. Those who cannot provide an initial sufficient paidbalance are denied access and an ability to place a call to begin with,even with respect to attempting to place the call for ringing only tosignal another party of a communication attempt. The present mobilecalling systems and methods provide access to such users to place a callusing the customized connection logic of asynchronous and/or synchronouscalling that permits the caller to place and momentarily complete a calleven with a zero balance and/or insufficient balance on a SIM card.

The present mobile calling systems and methods may service calls from afirst user mobile device that does not have a balance or paid airtime byimplementing a switching scheme on an Intelligent Network (IN) toautomatically modify and translate the call to include a routing prefixbased on a customized manual coding to address the switching node as asignaling node that delivers a communications protocol associated withthe customized connection logic. IN involves a telephone networkarchitecture with a call IN service logic that may be executed remotefrom switching facilities. A portion of the dialed number may trigger aservice request, such as an “800” toll-free portion being translatedinto a regular PTSN number. Embodiments described herein may furthermodify and translate the dialed number to include a routing prefix, andbased on a pre-configured manual number routing lookup table, to switchthe call to an asynchronous switching node to further process theservice request and automatically separate the call into a first portionbetween the caller and an asynchronous switching node and a secondportion, between the asynchronous switching node and the called party. Amanual routing entry, in a lookup table in the originating mobileswitch, is referenced to translate into a route and provide apre-configured route for the modified dialed number, for automatedprocessing by the asynchronous signaling switch. Translate as describedherein may be indicative of a routing and translation of a prefix withrespect to a mobile address. Furthermore, such a manual routing entrymay encompass a wildcard routing entry to catch and direct yet undefinedand not yet pre-configured routes to avoid a call routing failure. Thesystem may determine routing to occur for a number with more significantdigits to route over less significant digits (e.g., *1234 will takerouting precedence over *123). When a dialed sequence fails to match oneor more of the pre-configured defined routes in the manual routing entrylookup table, the wildcard entry may be utilized to route the modifiednumber to a catch-all route destination identifying the asynchronoussignaling switch. The routing entries, as described in greater detailbelow with respect to FIG. 1C, which illustrates an automated prefixing,routing, and switching scheme, including a loopback with a requirementof a routing table entry in the originating Mobile Switching Center(MSC) to which the connection code associated with the modified addressreferences. Reference to a Star Switch as an embodiment utilizing arouting prefix symbol of a star (*) before a dialed address maysimilarly apply disclosed protocols for other routing prefix embodiments(e.g., multiple stars and/or other symbols or numbers configured tomodify the dial address with a prefix, translate and route the modifiedaddress to the dialed party). As described below with respect to FIG.1C, prior to an MSC connecting the call to the modified route prefixedaddress, the MSC performs a digit analysis and pre-configured routingtable lookup to determine a trunk indicator (e.g., Trunk X) associatedwith the modified route prefixed address and routes the call along thetrunk indicator to a Gateway MSC (GMSC). The trunk indicator isindicative of a Trunk configured as a communication path (e.g., trunkcommunication path) to carry simultaneous multiple signals whileproviding a network access between two points, such as switches ornodes. The GMSC then routes traffic received along the designated Trunkbased on the trunk indicator to an IP address (for example, a SIP Trunkindication) of the asynchronous signaling switch, which then proceeds todeliver a flash signaling protocol to the receiving party as describedherein.

In one embodiment, a balance-independent SIM card is provisioned withoutairtime and does not require prepaid funds (e.g. a positive balance) andis configured to be controlled by an IN service logic to bypass billingwhile placing and completing a call. Additionally or alternatively, abalance-dependent (e.g., prepaid) SIM card provisioned with airtime thathas become depleted is also configured to be controlled by IN servicelogic while engaging a ring to place the call. Thus, even users withzero and/or insufficient balance (e.g., prepaid airtime) may place andcomplete a call. The asynchronous mobile calling systems and methodsdescribed herein implement the customized connection logic and switchingscheme to receive the call from the first user mobile device intendedfor the second user mobile device through the switching node, ring backto and disconnect from the first user mobile device, then ring forwardto and disconnect from the second user mobile device, where the firstuser mobile device is not charged for placement and completion of thecall.

Telephony calls in which at least two mobile device users may speak toone another may progress through a Basic Call State Model (BCSM) usingstandardized Points in Call (PICS), which are sequential steps at whichservice logic may be applied prior to further progressing a call. TheBCSM is a finite state machine, which with PICS permits a Mobile Switch(MSC) to interact with IN nodes to perform authentication, billingverification, and call progress monitoring. During a billingverification, the call may be paused to determine whether the account ofthe user placing the call has a sufficient balance or credit to continueand complete the call such that the call is permitted to advance andmature into a ringing state and an answered state. Billing systems maybe used that utilize rating engines and tables, including, but notlimited to, Online Charging Systems (OCS), and billing based onassociated Call Data Records (CDRS) to record transactions on a digitalnetwork. For a user with a balance-dependent (e.g., prepaid) accountthat is a zero balance or has otherwise insufficient funds, networkservices may be suspended and calls prevented until the user replenishestheir account. Embodiments of the mobile calling systems and methodsdescribed herein and in greater details below with respect to FIGS. 1-8permit such users and/or users without any prepaid account to place andconnect a call to engage ringing and incur zero costs through use ofassociated customized connection logic embodiments. As non-limitingexamples, (1) a prepaid SIM card may be utilized concurrently with abalance-independent SIM card, which is activated upon insufficient fundsbeing available, (2) a balance-independent SIM card may be used byitself such that a user is not required to prepay any funds to place acall, and/or (3) a dual function balance-independent-prepayable SIM cardmay be used that allows a user to place and complete a call withoutprepayment of funds, and also permits the user the option to receivefunds or prepay funds, to incur call charges if desired.

TABLE 1 below sets forth a glossary of acronym definitions and terms asutilized within this disclosure.

TABLE 1 AC Alternating Connect ACH Apply Charging ACM Address CompleteMessage ACK Acknowledgment ANS Answer API Application ProgrammingInterface BCSM Basic Call State Model BHCA Busy Hour Call Attempts CAMELCustomized Applications for Mobile network Enhanced Logic CDMA CodeDivision Multiple Access CDR Call Data Record CDRS Call Data Records CHTCall Hold Time CLI Calling Line Identity CLIP Calling Line IdentityPresentation CLIR Calling Line Identity Restriction CPG Call ProgressCSE CAMEL Service Environment CSI CAMEL Subscription Information DP2Detection Point 2 EDP-R Event Detection Point Request FLASH MomentaryConnect and Disconnect GMSC Gateway MSC GPRS General Packet RadioService GSM Global System for Mobile Communications GSMSCF GSM ServiceControl Function GSMSSF GSM Service Switching Function GSMSSG GSMService Selection Gateway HLR Home Location Register IAM Initial AddressMessage IMSI International Mobile Subscriber Identity IN IntelligentNetworking/Intelligent Network INITDP Initial Detection Point INAPIntelligent Network Application Protocol IP Internet Protocol ISDNIntegrated Services Digital Network ISUP ISDN User Part IVR InteractiveVoice Response MAP Mobile Application Part MC Mid Call MMS MultimediaMessaging Service MS Mobile Station MSISDN Mobile Subscriber ISDN MSCMobile Switching Center MO Mobile Originating MOD Modulus MSRN MobileStation Roaming Number MVNO Mobile Virtual Network Operator OBCSMOriginating Basic Call State Model OCS Online Charging System O-CSIOriginating Camel Subscription Information OFFHOOK Answering a call(Connect) ONHOOK Hanging up a call (Disconnect) OSS Operator SpecificService PDD Post Dial Delay PICS Points in Call PING Signaling CallerIdentity PSTN Public Switched Telephone Network RRBE Request Report BCSMEvent RAN Radio Access Network RBT Ring-back-tone RCS Rich CommunicationServices REL Release RLC Release Complete RTP Realtime TransportProtocol SBC Session Border Controller SCP Service Control Point SIMSubscriber Identification Module SIP Session Initiation Protocol SKService Key SLPI Service Logic Program Instance SMS Short MessageService SRF Specialized Resource Function SS7 Signaling System SevenSTAR SIM Zero Airtime SIM serviced by Star IN Logic TDMA Time DivisionMultiple Access UMTS Universal Mobile Telecommunications System URIUniform Resource Identifier USSD Unstructured Supplementary ServicesData VLR Visitor Location Register VOIP Voice Over Internet Protocol

Referring to FIG. 1A, an embodiment is disclosed of a prepaid (e.g.,balance-dependent) SIM card, which is activated when there is aninsufficient balance or funds available to use the prepaid SIM card.FIG. 1A works in conjunction with the method of FIG. 2, as described ingreater detail further below.

Referring again to FIG. 1A, flow items 100-103 are representative ofinitial steps to progress through by the prepaid SIM card system priorto progression to the flow items of FIG. 2. In flow item 100, the firstuser (e.g., user A) has a prepaid account associated with the prepaidSIM card and dials through the first user mobile device 820 a telephonenumber of the second user mobile device 824 of the second user (e.g.,user B). In flow item 101, the dual SIM card system is configured todetermine whether the prepaid SIM card has insufficient credit to placethe call. Referring to flow item 101, a servicing Mobile SwitchingCenter (MSC)/Global System for Mobile Communications (GSM) ServiceSelection Gateway (gsmSSG), hereinafter MSC/gsmSSG, received a callsetup request. It is contemplated by and within the scope of thisdisclosure that other cell phone service technologies such as CodeDivision Multiple Access (CDMA) may be utilized by the systems andmethods described herein. Referring back to flow item 101, onencountering an Initial Detection Point (e.g., as INITDP: D2 CollectedInfo) in the Originating Basic Call State Model (OBCSM), the MSCinitiates a dialog with an IN controller node associated with theprepaid SIM card. The IN controller node address, stored in the SIMprofile in home location register (HLR), is propagated together withother SIM profile data into the MSC/visitor location register (VLR)originating call subscription information record when the prepaid SIMcard registers and attaches to the network. The call setup requestencounters an IN credit verification in flow item 101 to query a balanceof the prepaid account associated with the prepaid SIM card of user A,to determine whether A has insufficient credit.

If the answer is No, such that the prepaid SIM card has sufficientbalance to place the call, the next step proceeds to flow item 104 tocontinue to place the call based on the prepaid SIM card and incurcharges to the prepaid SIM card for any air time consumed once the callis answered. Thus, if the prepaid account associated with the first usermobile device 820 of user A has sufficient balance or credit to completethe call, the flow progresses from flow item 101 to flow item 104. Asthe prepaid account of user A has sufficient balance or credit, the INcontrolling node issues a Continue command to permit the call tocontinue based on that SIM card. This Continue command instructs the MSCto route the call to the second user mobile device 824 of user B.

However, if the answer is Yes, such that the prepaid SIM card hasinsufficient balance to place the call, the SIM card system isconfigured to implement a routing protocol in flow item 102 to implementa switch in flow item 103 momentarily complete the call, e.g., withoutincurring a charge. Thus, if the prepaid account associated with thefirst user mobile device 820 of user A has insufficient balance (e.g.,prepaid or credit) to complete the call, the flow progresses from flowitem 101 to flow item 102. The IN controlling node is configured toautomatically modify the telephone number associated with the seconduser mobile device 824 of user B to incorporate a routing prefix, suchas a Star (*) routing prefix in an embodiment. The modified telephonenumber with the routing prefix is configured to route the call to theStar Switch of flow item 103. The IN controlling node is configured tocommand the MSC to Connect the call on the modified telephone number,such as through a Connect *B command.

In the embodiment using the Star (*) routing prefix, such Star prefixednumbers may route based on a wildcard entry in an MSC routing table thatpoints undefined numbers to the Star Switch of flow item 103 for furtherprocessing. Since a Star routing entry on the MSC may permit users tomanually star phone numbers and thereby selectively route their calls tothe Star Switch and invoke an associated flash communications protocol(to permit a signaling to the user B of a missed or ringing call attemptfrom user A, as described below), the modified telephone number as amodified routing address may utilize multiple stars or other routingprefixes to distinguish user versus network flash invocation.

By way of example, and not as a limitation, the IN controlling node isconfigured to modify the B address with a double (**) or a triple (***)star prefix, the latter symbolically representing zero balance ($0.00)calls. Either differentiating prefix may permit network invoked flashes(e.g., permitted ring signals) to be separately audited from thoseinvoked by users manually star prefixing calls. Any uniquely identifyingprefix may be applied separately or in combination to the star prefixes,including, but not limited to, internal numerical routing prefixes.

Referring to flow item 103 of the Star Switch, the MSC is configured toperform a routing lookup on the star prefix utilized, and route the callto the Star Switch, which conducts the communications protocol describedwith respect to FIG. 2 in greater detail below.

Referring to FIG. 1B, an example of an embodiment is disclosed of abalance-independent SIM card that may be used by itself such that a useris not required to prepay any funds to place a call. FIG. 1B shows aflowchart of a method for a balance-independent SIM card (e.g., a StarSIM) that continues on to work in conjunction with the method of FIG. 2as described in greater detail further below.

Referring again to FIG. 1B, flow items 110-113 are representative ofinitial steps to progress through by the balance-independent SIM cardsystem, prior to progression to the flow items of FIG. 2. In flow item110, the first user (e.g., user A) has a first user mobile device 820with a balance-independent SIM card configured to be serviced by an INcontroller. The first user (e.g., user A) dials through the first usermobile device 820 a telephone number of the second user mobile device824 of the second user (e.g., user B) as the dialed address.

In flow item 111, on encountering the INITDP in the OBCSM, the MSC isconfigured to initiate a call control dialog with a Star IN controllingnode associated with the balance-independent SIM card. The associated INnode address is stored in the HLR/VLR originating subscriptioninformation record.

In flow item 112, as the balance-independent SIM card is configured tooperate without airtime, the Service Logic for the Star IN controllingnode does not conduct or require a credit verification, and isconfigured to directly proceed to modify the user B telephone numberaddress to incorporate a routing prefix and commands the MSC to connectthe call using the modified address as described herein.

In flow item 113, the MSC is configured to perform a routing lookup onthe address prefix and route the call to the Star Switch, which conductsthe flash communications protocol as described in greater detail furtherbelow with respect to FIG. 2. The routing lookup may reference apre-configured routing lookup table to determine the translation anddirection of the translated number, to the asynchronous signalingswitch.

Such a Star IN controlling node is thus configured to singularly commandthe originating MSC to CONNECT the call on the modified address. Whilethe star (*) symbol prefix is used in an embodiment, in otherembodiments the prefix may be translated into or replaced with aninternal routing code identifying the Star Switch. Any network routingcode prefix that uniquely identifies and addresses the Star Switch maybe utilized.

Referring to FIG. 1C, a prefixing, routing, and switching scheme for thezero charge SIM card system of FIG. 1A or the balance-independent SIMcard of FIG. 1B is shown. In some embodiments, a dualbalance-independent-prepayable SIM card may be used that allows a userto place a call without either prepayment or sufficient credit, but alsopermits the user the option to prepay and incur call charges if desired.

The prefixing, routing, and switching scheme for the zero charge SIMcard system that may be used with either FIG. 1A or FIG. 1Bmethodologies includes a flow item 130, in which user A dials throughthe first user mobile device 820 a regular Mobile Subscriber IntegratedServices Digital Network (MSISDN) telephone address of the second usermobile device 824 of user B to generate a call setup request betweenuser A and user B. In flow item 131, a servicing MSC is configured toreceive the call setup request. In flow item 132, the MSC is configuredto enter the BCSM, encounter Detection Point 2 (DP2), and establish anINITDP dialog with a service control point (SCP) controller. In flowitem 133, the SCP controller is configured to perform a balance orcredit verification to determine whether user A has insufficient balanceor credit to complete the call.

In flow item 134, in response to this zero balance condition when theSCP controller determines user A has insufficient balance or credit toplace the call, the SCP controller is configured to modify the B addresswith a prefix, such as a star (*) prefix. Further, in flow item 134, theSCP controller may be configured to suppress an insufficient balancenetwork announcement to user A based upon the determination that user Ahas insufficient balance or credit to place the call.

In flow item 135, the SCP is configured to command the MSC to connectthe call to the modified telephone address (e.g., the star prefixedaddress or other prefix type modified address). In flow item 136, onreceiving the connect command from the SCP, the MSC is configured toperform a digit analysis and routing table lookup based on the modifiedtelephone address including the utilized prefix (e.g., the star prefix).In flow item 137, the routing table is configured to return a Trunkidentifier (X) associated with the modified telephone address (e.g., thestar route). In flow item 138, the MSC is configured to route the callalong the Trunk X to the GMSC (e.g., the SIP Trunk). In flow item 139,the GMSC is configured to route traffic received along the Trunk X tothe IP address of the asynchronous signaling switch (e.g., the StarSwitch IP address). In flow item 140, the Star Switch is configured todeliver a flash signaling protocol to permit engaging and placing of thecall as described in greater detail below with respect to FIG. 2.

Referring to FIG. 2, a flowchart of a method for continuing the methodof FIG. 1A or FIG. 1B and upon using the prefixing, routing andswitching scheme of FIG. 1C is shown. Thus, FIG. 2 continues the processof using the modified switch routing to place and complete a call, andengage a ring, without incurring a charge or cost to the accountassociated with the first user mobile device 820 placing the callthrough either the balance-dependent (e.g., prepaid) SIM card of FIG.1A, or the balance-independent (e.g., star) SIM card of FIG. 1B.

In flow item 200, the Star Switch is configured to logically andphysically decouple the call originating/uplink (left side) andterminating/downlink (right side) legs by signaling them independently,in the backward direction to the caller and in the forward direction tothe called, along distinct routes of flow items 210 and 260,respectively. These two independent call paths may be signaledsubstantially simultaneously.

In flow item 210, which describes the process along the independent callpath between the first user mobile device 820 and the switching node asthe originating call setup leg, the MSC is configured to route to theStar Switch via a Gateway Mobile Switching Center/Session BorderController (GMSC/SBC), and the Star Switch is configured to respond byinstantly presenting a ring-back-tone (RBT) to user A. The RBT generatesa preemptive ring signal to provide comfort to user A that the call isaccepted and is being presented to user B.

In flow item 220, the Star Switch is configured to determine via aconfiguration setting whether a native MSC CDR generation on theoriginating carrier network is requested. If a CDR is not requested perthe Star Switch configuration, the call flows to flow item 240. However,if the CDR generation option is set, the call flows to flow item 230 andthe Star Switch is configured to answer the call by going OFF HOOK.Answering the call starts a call duration timer that records theduration of the connected (answered) call.

The call then flows to flow item 240, in which the Star Switch isconfigured to then hang up the call if progressing through flow item 230by going back ON HOOK momentarily thereafter. Since a CDR typicallyrecords call durations in increments of 1 second, milliseconds areeither rounded up or down to the nearest second. In order to generate,for example, a zero second CDR, the Star Switch may simply disconnectthe call within 500 milliseconds (ms). To cater for signaling latency,such a zero second CDR embodiment would substantially connect anddisconnect within milliseconds. For example, the call may be answeredand then disconnected 100 ms thereafter. The present disclosuredescribes a manner to generate and suppress billing for unanswered callsthrough the MSC recording these early CDRS. For example, the HOOK FLASHsignaling permits carriers to generate native zero second CDRS on theMSC for recording these such signaled calls.

During flow item 240, the Star Switch is configured to disconnect thecall. If the call was previously answered in flow item 230, the statereturns to ON HOOK. Otherwise if progressing directly between flow items220 and 240, the call is terminated without answering and theoriginating/uplink leg of the call is complete. Thus, in flow item 250,the first user mobile device 820 is serviced and disconnected from thecall.

With respect to the terminating/downlink leg on the right side betweenthe Star Switch and the second user mobile device 824, flow item 200progresses to flow item 260. In parallel to signaling on the uplink asshown through flow items 210-250, the Star Switch is configured toestablish a call leg on the downlink path towards a destination to thesecond user mobile device 824 of user B. The call to user B is set withcalling line identity for user A associated with the first user mobiledevice 820 and extracted from the uplink request signal. The call routesvia an SBC/GMSC to the network of user B.

In flow item 270, the Star Switch is configured to respond to indicationthat the second user mobile device 824 of user B is ringing or otherwisealerting the user B of an incoming call identifying the user A. In flowitem 280, in response to mobile device 824 ringing, the Star Switch isconfigured to cancel the call. In flow item 290, cancelling the callreleases and completes the downlink dialog and leg, which has nowsuccessfully deposited a ring bearing the calling line identity of userA at the destination second user mobile device 824 of user B.

Thus, referring to FIG. 2, in one embodiment, the user A attempting toplace a call to the second user mobile device 824 of user B as thecaller from the first user mobile device 820 is switched ON/OFF the airprior to the system alerting user B. In an embodiment, the systemswitches and signals the zero airtime call to deliver an asynchronousflash communication with user A and user B through the followingsequence of steps. With respect to user A, the call from the first usermobile device 820 of user A is disconnected via the switching node inthe backward (originating/uplink) direction to user A, e.g, after onering. With respect to user B, the call to the second user mobile device824 of user B is disconnected via the switching node in the forward(terminating/downlink) direction to user B, e.g, after one ring. Such anasynchronous and disconnected communication protocol is configured toprevent the call from progressing to speech, i.e., as would generallyincur a charge, as the protocol prevents user A from being directlyconnected through to user B. Since the originating and terminating callphases are logically and physically decoupled such that they areswitched, signaled and disconnected independently, the disclosed methodsand systems are asynchronous and do not establish synchronous end to endconnectivity directly between users A and B. Thus, user A is not onlinewhen the second user mobile device 824 of user B rings. Through theprotocols disclosed herein, billing may be reversed on callback fromuser B to user A, such that revenue may flow from zero airtime events ofthe signaling call from user A to user B.

Further, while the RBT provides user A with auditory confirmation, theautomatic disconnect provides user A with visual confirmation that therequest was serviced to completion. In an embodiment in which user A asthe caller is switched ON and OFF the airwaves in just one second, eventhough the B party has yet to be alerted, the preemptive and acceleratedRBT comforts the user that the call is being made to user B by theswitching node.

If the Star Switch is unable to contact the second user mobile device824 of user B on the downlink leg of FIG. 2, the call may automaticallyenter a retry schedule. Automatically retrying such failed call attemptson behalf of the user A may attenuate repetitive manual redialing byuser A. Such repetitive manual redial behavior may spiral into anegative feedback loop that exacerbates network load and busyconditions, resulting in more and more failed call attempts. Thepreemptive RBT and automated retry solution, for example, on a retryschedule, as disclosed, delivers accelerated asynchronous digitalringing.

The Star Switch signaling of FIG. 2 is described in greater detail withrespect to FIGS. 3A and 3B below, which depict step ladder sequences forflash signaling embodiments for respectively the prepaid call withinsufficient balance and the balance-independent SIM card ofcorresponding FIGS. 1A and 1B.

Referring to FIG. 3A, a control scheme illustrating a sequential stepladder structure utilizing the methods of FIG. 1A and FIG. 2 is shown.In flow item 310, the first user has a prepaid user account associatedwith the first user mobile device 300 (e.g., an embodiment of the firstuser mobile device 820) and dials a telephone number of the second usermobile device 308 (e.g., an embodiment of the second user mobile device824) of user B. The first user mobile device 300 of user A is configuredto transmit a call setup as a Mobile Originating (MO) to the servicingMSC 301. The setup message contains the signals such as the telephoneaddress of user B in addition to other call parameters. The MSC entersthe OBCSM encountering the INITDP.

In flow item 311, the INITDP opens a call control dialog with PrepaidService Control Point (SCP) 302, the address of which is recorded in theSIM subscription information in the MSC/VLR 301.

In a customized applications for mobile networks enhanced logic (CAMEL)setting, the system may employ standards that work on a Global Systemsfor Mobile Communications (GSM) core network or the Universal MobileTelecommunications System (UMTS) network. In a CAMEL O-CSI (OriginatingCamel Subscription Information) embodiment, the MSC has an associatedgsmSSF (GSM Service Switching Function), and the SCP is referred to asthe gsmSCF (GSM Service Control Function). The SCP 302 is configured toperform a credit verification for user A, for example, by querying anOnline Charging System (OCS) 303, or a Prepaid Billing System, todetermine whether an account associated with user A has sufficientcredit to complete the call. While SCP 302 and OCS 303 are depicted asseparate nodes, they may be the one and same logical or physical node,and they may embody both call and billing control.

In flow item 312, in response to the credit check, the OCS 303 mayrespond to the SCP 302 that user A has insufficient credit. In responseto the credit insufficiency, the SCP modifies the mobile address of userB with a prefix identifying the Star Switch 305 and instructs the MSC301 to connect the call using the supplied modified address.

In flow item 313, the MSC 301 performs a routing lookup on the prefix todetermine a trunk/route to the Star Switch 305, which may be hosted inthe Cloud (e.g., as described in greater detail below with regard toFIG. 8), and transmits an Integrated Services Digital Network User Part(ISUP) IAM (Initial Address Message) to the GMSC/SBC 304, which beginsthe uplink dialog 324. The GMSC/SBC 304 is configured to interworkbetween a Signaling System Seven (SS7) and an IP network, and in oneembodiment, to perform signaling translation between ISUP and SIP(Session Initiation Protocol). In such an ISUP/SIP translation, ISUP IAMis translated into SIP INVITE, which is transmitted to the Star Switch305. The ISUP includes messaging protocol such as IAM and is a part ofSS7 used to set up telephone calls in a public switched telephonenetwork (PSTN). A Mobile Application Part (MAP) may be used as an SS7protocol to setup and control calls via the PSTN through providing anapplication layer for GSM and UMTS mobile core networks and generalpacket radio service (GPRS) core networks for communication between andservicing of mobile users. Telephone exchanges (e.g., switches) may beconnected via T1 or E1 trunks as shared communication line paths totransport speech from calls. SIP is a signaling protocol to initiate,maintain, and terminate real-time multi-media (e.g., voice, video,and/or messaging) sessions for internet telephony applications and/orinstant messaging over Internet Protocol (IP) networks and/or voice overIP (VOIP) networks.

In flow item 314, on receiving the SIP INVITE, the Star Switch 305 isconfigured to respond with a SIP 180/RINGING message in the backwarddirection, which may be instantaneous, and which commands the GMSC/SBC304 to return an ISUP Address Complete Message/Call Progress (ACM/CPG)Alerting message notifying the MSC 301 that the destination is ringing.In turn, the MSC 301 presents a RBT to the first user mobile device 300of user A. In responding with SIP/180 as a ringing message, the StarSwitch 305 matures the call into a placed and completed call (asuccessful call setup).

In flow item 315, when a native CDR generation at MSC 301 is required,the Star Switch 305 in one embodiment is configured to wait one secondafter issuing the SIP/180 code and then commands the GMSC/SBC 304 toconnect the call by issuing a SIP 200/OK code, which in turn istranslated into an ISUP Answer (ANS) message at GMSC/SBC 304 to notifythe MSC 301 that the call has been answered. At this point, the call hasgone OFF HOOK, and a call duration timer begins for CDR generationassociated with the answered call.

In flow item 316, the Star Switch momentarily thereafter disconnects thecall by issuing a SIP BYE command in the backward direction, which theGMSC/SBC translates into ISUP REL (Release) to instruct MSC 301 torelease the call, which returns the call to an ON HOOK state. Such hookflash signaling is implemented via lifting the receiver to be OFF HOOK(e.g., answered), and then momentarily thereafter replacing the receiverback to be ON HOOK (e.g., released).

In flow item 317, on disconnecting the call, the MSC 301 responds withISUP RLC (Release Complete), which is translated at the GMSC/SBC 304into an ISUP 200 code and transmitted to the Star Switch to close theuplink dialog 324. In flow item 318, if CDR generation was indicated,upon issuing SIP 200/OK, the MSC 301 completes the call data recording(CDR). The resultant CDR may record a zero or one second call duration.The uplink dialog 324 may be collectively referenced herein as a “RingFlash Hook” signaling protocol 324, in which user A as the callerreceives an instant ring, followed by a momentary connect and disconnect(OFF/ON Hook Flash), clearing the call and displaying a 0:00 second callduration on the caller display. While the RBT may provide an auditoryconfirmation to user A of the placed call, such flash zero second callduration from the call that instantly rises and drops is able to providea visual confirmation to user A that the request was serviced tocompletion, that the call is being placed to user B via the switchingnode (e.g., Star Switch 305). While the uplink dialog 324 may occur insequence, the downlink dialog 325 may be signaled in parallel.

Referring again to flow item 313, on receiving the Uplink SIP INVITEfrom the GMSC/SBC 304, the Star Switch 305 may be configured to invokethe downlink dialog 325 by issuing SIP INVITE in the forward directionto SBC/GMSC 306, with the first user mobile device 300 of user A set inthe From: header, and the second user mobile device 308 of user B set inthe To: Header (and in the SIP Uniform Resource Identifier (URI), theSIP addressing schema character string identifying a call recipient). Ifthe second user mobile device 308 of user B is currently roaming (e.g.,attached) on the same network as the first user mobile device 300 ofuser A, then SBC/GMSC 306 and GMSC/SBC 304 are typically the one and thesame gateway.

In flow item 320, the SBC/GMSC 306 is configured to translate the SIPINVITE into ISUP IAM to route the call toward the servicing destinationMSC 307, which in turns pages and locates the second user mobile device308 of user B to setup the call through control channel signaling. Inflow item 321, when the second user mobile device 308 of user B isalerted to the incoming call, the MSC 307 signals ISUP ACM/CPG, alertingin the backward direction to SBC/GMSC 306, which translates into a SIP180/RINGING signal sent to the Star Switch 305. In flow item 322, onreceiving ringing indication, the Star Switch 305 responds with SIPCANCEL in the forward direction, which is translated into ISUP REL atSBC/GMSC 306 and sent to the MSC 307. The MSC 307 then releases thecall. On releasing the call, the Star Switch 305 has successfullydeposited the Calling Line Identity (CLI) of the first user mobiledevice 300 of user A at the second user mobile device 308 of user B,which in turn is configured to display a resulting missed call from thefirst user mobile device 300 of user A.

In flow item 323, the MSC 307 is configured to acknowledge the callrelease by signaling ISUP RLC in the backward direction to SBC/GMSC 306,which in turns transmits a SIP 200 code backward to the Star Switch 305.The SBC/GMSC 306 then may transmit a SIP 487/TERMINATION code to theStar Switch 305 to signal dialog termination. The Star Switch 305 isconfigured to acknowledge termination by sending a SIP ACK code to theSBC/GMSC 306, which may complete the flash protocol associated with thedownlink dialog 325.

In an Analog Synchronous Ringing scheme establishing a direct end to endconnection between devices of users A and B, where user A dials user Band waits for the destination to ring before disconnecting, the entiretransaction may take, for example, between 5 and 15 seconds. During thissynchronous transaction period, the device of user A may consume scarceRadio Control Channels. In the Digital Asynchronous Ringing protocoldescribed herein, the device of user A is signaled and switchedindependently from signaling and switching to the device of user B toreduce an amount of time such Radio Control Channels are consumed. Inpresenting preemptive RBT to user A and instantly disconnecting thecall, the first user mobile device 300 of user A may be switched ON/OFFthe air in just 1 second on the uplink, since the second user mobiledevice of user B is signaled independently on the downlink, whichassists with respect to Busy Hour Call Attempts (BHCA). BHCA is anindustry metric quantifying the number of call attempts a network canprocess during the Busy Hour. The Star Flash Protocol described hereinmay reduce a Call Hold Time (CHT) from, on average, 10 seconds down tojust 1 second to recover vast originating wireless spectrum availabilityand airtime. In embodiments, such spectrum recovery may deliver 10XBHCA, permitting an order of magnitude more calls to be signaledutilizing the same wireless spectrum (e.g., radio access network (RAN)).

Referring to FIG. 3B, a control scheme illustrating a sequential stepladder structure utilizing the methods of FIG. 1B and FIG. 2 is shown.In flow item 340, the first user has a balance-independent SIM cardaccount associated with the first user mobile device 330 (e.g., anembodiment of the first user mobile device 820) that does not require orincur airtime cost and dials a telephone number of the second usermobile device 338 (e.g., an embodiment of the second user mobile device824) of user B. The first user mobile device 330 of user A is configuredto transmit upon such dialing a call setup to the servicing MSC 331. Thesetup message contains the mobile address signals of user B in additionto other call parameters. The MSC 331 enters the Originating Basic CallState Model (OBCSM) encountering the Initial Detection Point (INITDP).

In flow item 341, the INITDP opens a call control dialog with StarService Control Point (SCP) 332, the address of which is recorded in theSIM subscription information in the MSC/VLR 331 (e.g., as OriginatingCamel Subscription Information CAMEL O-CSI). In a CAMEL O-CSIembodiment, the MSC 331 has an associated gsmSSF (Service SwitchingFunction), and the SCP is referred to as the gsmSCF (Service ControlFunction). The Star SCP 332 short circuits and does not require a creditverification for the account associated with the first user mobiledevice 330 of user A, which might otherwise query an Online ChargingSystem (OCS) 333 to determine whether an account associated with user Ahas sufficient credit to complete the call. While SCP 332 and OCS 333are depicted as separate nodes, they may be the one and same logical orphysical node, embodying both call and billing control.

In flow item 342, a Star SIM call (e.g., balance-independent SIM cardprovisioned with zero airtime and serviced with Star IN logic asdescribed herein) has no billing requirement, and the Star SCP 332 shortcircuits billing verification as described herein to directly andautomatically modify the B party address with a prefix identifying theStar Switch 335 and instruct the MSC 331 to connect the call using thesupplied modified address. Reference to “Star,” “Star Sim,” or “Star INlogic” as described herein may utilize a star (*) routing prefix orutilize alternative routing prefixes to progress through the modifiedprefix protocols as described herein. In flow item 343, the MSC 331 isconfigured to perform a routing lookup on the prefix to determine atrunk/route to the Star Switch 335, which may be hosted in the Cloud,and transmit an ISUP IAM to GMSC/SBC 334.

Flow items 344-353 of FIG. 3B operate similarly to flow items 314-323 ofFIG. 3A. Further, the uplink dialog 354 and downlink dialog 355 operatesimilar to the uplink dialog 324 and downlink dialog 325 of FIG. 3A.FIGS. 3A and 3B thus differ in that FIG. 3B excludes a creditverification using OCS 333 in FIG. 3B, whereas FIG. 3A requires thecredit verification during the call setup. Thus, billing nodes such asOCS 333 may be bypassed and not stressed by applications not requiringbilling verification during the initial call setup as in FIG. 3B.

The signaling protocols with respect to the uplink dialogs 324, 354 anddownlink dialogs 325, 355 of FIGS. 3A and 3B are further respectivelydescribed in FIGS. 4A and 4B, which tabulate source code leveltranslation sequences between ISUP and SIP protocols for the uplink anddownlink legs.

Referring to FIG. 4A, a control scheme for an originating flash hookprotocol for the control schemes and uplink dialogs 324, 354 of FIG. 3Aor 3B is shown. FIG. 4A illustrates an ISUP to SIP uplink signalingembodiment. Column 400 is representative of an originating networkoperator as a carrier, which receives the zero airtime call request asdescribed herein. Column 401 is indicative of the signaling directionwith respect to the carrier of Column 400. Column 402 is representativeof the signaling conducted by the Star Switch 305, 335 of FIGS. 3A, 3B.Column 403 is representative of a delta time (e.g., change in time) thatelapses between a previous and current signal. Column 404 is indicativeof notative commentary associated with flow items 405-410 describedbelow.

In flow item 405, on receiving a call setup request from the first usermobile device 300, 330 of user A addressed to the second user mobiledevice 308, 338 of user B, and after encountering or short circuiting acredit verification as described herein respectively with respect toFIGS. 3A and 3B, the originating network applies a routing prefix (suchas *) to the mobile address of the second user mobile device of user Band routes the call to the Star Switch signaling ISUP IAM (e.g., A,*B)in the forward direction (e.g., carrier EGRESS in Column 401) via theGateway MSC/SBC 304, 334. On receiving the ISUP IAM, the GMSC/SBC 304,334 translates the signal into SIP INVITE (A,*B) in Column 402 andtransmits the signal to the Star Switch 305, 335.

In flow item 406, on receiving the SIP INVITE, the Star Switch 305, 335,may respond with a SIP 100/TRYING signal in the backward direction(e.g., carrier INGRESS in Column 401) to arrest an INVITE timeout. Azero (0) milliseconds (ms) delta between receiving the INVITE andresponding with the 100/TRYING is illustrative of an immediate response.The GMSC/SBC 304, 334 may translate SIP 100/TRYING into ISUP ACM sent inthe backward direction towards the MSC 301, 331.

In flow item 407, substantially simultaneously, the Star Switch 305, 335may be configured to transmit SIP 180/RINGING in the backward directionto the first user mobile device 300, 330 of user A to signal to the MSC304, 334 that the destination of the second user mobile device 308, 338of user B is being alerted. On receiving the SIP 180/RINGING, theGMSC/SBC is configured to transmit an ISUP CPG ALERTING signal in thebackward direction to the Carrier MSC. ISUP CPG/ALERTING presents a RBT(ring-back-tone) to the caller (e.g., user A of the first user mobiledevice 300, 330). Whether 180/RINGING is signaled alone or inconjunction with 100/TRYING, such an immediate response delivers aninstant Post Dial Delay (PDD) response, herein termed a zero PDD.

In flow item 408, after responding with SIP 180/RINGING, the Star Switch305, 335 may be configured to pause, such as for 1000 ms, to permit theringing presentation as the RBT to user A. The 1000 ms delta may beshortened or extended to control ringing duration at the first usermobile device 300, 330 of user A. If native carrier CDR generation isrequired on the originating MSC 301, 331 as described herein, the StarSwitch 305, 335 may then go OFF HOOK (e.g., be answered) by signalingSIP 200/OK in the backward direction to the GMSC/SBC, which in turntranslates the signal into the ISUP ANS message. On receiving the ISUPANS message, the originating MSC 301, 331 begins a call durationrecording timer for CDR generation.

In constructing the SIP 200/OK response, which establishes a RealtimeTransport Protocol (RTP) media stream, the Star Switch 305, 335 mayblackhole the media by specifying IP address 0.0.0.0 in the SDPconnection address line (e.g., c=IN IP4 0.0.0.0). This zero IP addresshas the property that packets sent to it will never leave the host thattransmits them and rather are simply discarded (e.g., black holed). Inblackholing the media sent from the carrier MSC/GMSC, the Star Switch305, 335 forgoes the need to support the more bandwidth intensive mediapackets, enabling the Star Switch 305, 335 to operate entirely withinthe SIP signaling domain at scale.

In flow item 409, after going OFF HOOK (e.g., the call being answered),the Star Switch 305, 335 may shortly return to an ON HOOK state (e.g.,the call being released) by signaling SIP BYE to the carrier, which theGMSC/SBC translates into ISUP REL, releasing the call and closing theCDR ticket. A delta less than 400 ms, catering for signaling latency,may ensure that a CDR is recorded with a sub 500 ms duration timer. Thecall duration timer may round up or down to the nearest second, suchthat signaling OFF/ON HOOK within this sub-second window generates azero or one second CDR.

Even if CDR generation was not required, the Star Switch 305, 335 stillis configured to signal SIP BYE to terminate the call rather thanterminating a call using other SIP 4XX signals, such as user busy (SIP486) or call terminated (SIP 487). Even with use of a BYE response soearly on in a call setup, the Star Switch 305, 335 has already maturedthe call into a dialog by signaling SIP 180/RINGING, which necessarilyincorporates a SIP To: Tag. Per SIP RFC, dialogs are created through thegeneration of non-failure responses to INVITE requests. Within the SIPspecification embodiments, only 2XX and 101-199 responses with a To tag,may establish a dialog, and dialog establishment permits a UAS torespond with BYE, even though the SIP BYE may be signaled prior toreceiving a SIP ACK (Acknowledgement) to a SIP 200/OK when the latter issignaled. Use of SIP BYE may instantly and cleanly clear the call anddisplay a duration of 0:00 seconds on the first user mobile device 300,330 of user A, which assists to deliver a visual confirmation to user Athat the call was serviced to completion.

In flow item 410, on receiving the ISUP REL, the MSC 301, 331 releasesall associated call resources and acknowledges termination by sending arelease complete ISUP RLC message in the forward direction, which theGMSC/SBC 304, 334 translates into SIP 200 (with a Cseq BYE headerfield). On receiving the SIP 200 confirmation, the Star Switch uplinkdialog 324, 354 completes.

In embodiments, native CDR generation on the originating carrier MSC301, 331, permits independent carrier audited reconciliations between ABflashes from user A to user B and any BA callbacks from user B to userA. As a non-limiting example, where Tx represents a datetime stamp, T0may indicative of a zero airtime user A dialing user B at a datetime T0.The CDR date-time stamp may incorporate at least YYYYMMDDHHMMSSMMM,where YYYY is the current year, MM the current month, DD the currentday, HH the current hour, MM the current minute, SS the current secondand MMM the current millisecond.

In utilizing HOOK FLASH (OFF/ON HOOK) signaling as disclosed herein, theStar Switch 305, 335 commands the MSC 301, 331 to generate a CDRrecording the flash communication between the first user mobile device300, 330 of user A and the second user mobile device 308, 338 of user Bat T0 for a duration of 0 or 1 seconds, which generates an OriginatingCDR that may be titled (e.g., labeled and tracked) as A*B-T0D0. All suchflash signaling generated CDRS may collectively describe the Star CDRSet.

In one embodiment, the Star prefix may be translated (e.g., mapped) intothe associated Trunk X routing code, and as such the CDR would berecorded as AXB-TD, where X is the associated routing code. TheOriginating CDR is thus one of a plurality of call data recording codesthat may be tracked to the audit and reconcile the call charges to thesecond user mobile device 308, 338 of user B upon callback as describedherein.

T1 may be indicative of a timestamp associated with the user B returningthe ring by calling back user A at datetime T1. By way of example, andnot as a limitation, user A may answer the call and engages in dialogwith user B for a duration of 90 seconds. This switched call may then bebilled to and paid for by user B through generation of an originatingand a terminating CDR that may be titled as BA-T1D90 as another one ofthe plurality of call data recording codes.

T2 may be indicate of a timestamp associated with user B returning asecond call back to A at a datetime T2. For example, user A may answerthe call and engage in further dialog with B for a duration of 120seconds, wherein the call generates another originating and terminatingCDR that may be titled as BA-T2D120 as another one of the plurality ofcall data recording codes.

A Carrier A may utilize the titles to calculate a revenue generated bythe flash call ping of user A to user B (e.g., A*B-T0) by reconcilingall callback CDRS of calls returned from user B to user A (e.g., BA-Tx)against the Star CDR Set, within a specified window of time. As anon-limiting example, to calculate all callbacks received within 1 hourof A*B-T0, Carrier A may extract and sum call durations Dy for any BA-TxCDR where Tx-T0 is less than or equal to 60 minutes (e.g., 1 hour). Forreconciling callbacks received within other periods of time, such as 2hours, 12 hours, etc., Carrier A may similarly sum all durations Dy forall Tx-T0 less than or equal to that other period of time. As anothernon-limiting example and in embodiments, the CDR reconciliation, on theA*B flash communication at T0, may return two calls BA-T1D120 andBA-T2D90, totaling 210 seconds.

Referring to FIG. 4B, a control scheme for a terminating flash hookprotocol for the control schemes and downlink dialogs 325, 355 of FIG.3A or 3B is shown. FIG. 4B illustrates a SIP to ISUP downlink signalingembodiment. Column 440 is representative of signaling at the Star Switch305, 335 controlling the downlink dialog 325, 355. Column 441 isindicative of the signaling direction with respect to the terminatingCarrier of Column 442. Column 442 is representative of the signalingtranslation performed at the Carrier Gateway. Column 443 isrepresentative of the delta time that elapses between a previous and thecurrent signal, and Column 444 is indicative of notative commentaryassociated with flow items 445-449 described below.

In flow item 445, the Star Switch 305, 335 is configured to extract theaddress signals from the INVITE received on the Uplink and initiate adownlink call in the forward direction (e.g., Carrier INGRESS in Column441) to the terminating carrier gateway SBC/GMSC 306, 336 using the SIPINVITE addressed from A to B. Determining the route required to setupthe call may include a GMSC Global Title Translation to determine theuser B HLR, querying the B HLR for the current destination MSC/VLRaddress to which user B is attached, receiving from the HLR the MSCaddress and Mobile Station Roaming Number (MSRN), and paging andlocating the second user mobile device of user B as cellular events. TheGMSC is configured to translate the SIP INVITE into ISUP IAM towards thedestination MSC/VLR.

In flow item 446, the GMSC is configured to respond with SIP 100/TRYINGin the backward direction to the Star Switch 305, 335 to arrest anINVITE timeout. While FIG. 4B shows the 100/TRYING following ISUP IAM,this is merely one illustrative embodiment to show that INVITE istranslated and mapped into ISUP IAM. A GMSC/SBC may respond with SIP100/TRYING on receiving an INVITE. In embodiments, any call progressingsignals (SIP18X) that may precede SIP 180 are omitted for clarity.

In flow item 447, on receiving notification that the second user mobiledevice 308, 338 of user B is ringing, the MSC 307, 337 sends ISUPCPG/ALERTING in the backward direction to the GMSC 306, 336, which theGMSC translates into SIP 180/RINGING and sends to the Star Switch 305,335. In flow item 448, on receiving SIP 180/RINGING, the Star Switch305, 335 may instantly respond with SIP CANCEL in the forward directionto the GMSC 306, 336, which commands the call to be released. The GMSC306, 336 may translate this command into ISUP REL and send thetranslated command to the MSC 307, 337.

In embodiments, an immediate zero (0) ms delta response may deliver aflash ring on the second user mobile device 308, 338 of user B, whichmay simply flash the call on the device display of the second usermobile device 308, 338 with or without emitting an audible ring. Theassociated delta time may be extended, such as, for example, to 1000 ms,to permit time for an audible ring alert. For example, a 1000 ms deltamay permit delivery of one ring whereas a 0 ms delta may permit deliveryof zero rings and instead flash a missed call alert onto the display ofthe second user mobile device. Combinations of ringing and flashingalerts may be utilized. In one embodiment, such a delta signaling timingparameter may be programmatically switched between 0 ms and 1000 msbased on a time of day. The delta may be set to 1000 ms during daylighthours to emit an audible ring and set to 0 ms during evening andnighttime to silently flash ring and not disturb the recipient. Such adynamically timed flash signaling embodiment may be able to deliver avirtual flashlight feature that is switched off during the day(permitting ringing the device) and on during the night (permittingflashing the device).

In flow item 449, on releasing the call, the MSC 307, 337 is configuredto transmit ISUP RLC in the backward direction to the GMSC 306, 336,which in turn translates this into SIP 200 (Cseq: CANCEL) transmittedbackwards to the Star Switch 305, 335. GMSC may then finalize the dialogsending a SIP 487/TERMINATED signal in the backward direction to theStar Switch 305, 335. The Star Switch 305, 335 may then acknowledge thetermination with SIP ACK in the forward direction to complete thedownlink dialog 325, 355.

In an embodiment, the switching systems and methods described herein mayoperate on a parallel path to a positive balance or prepaid accountsystem. Such an account system may be predicated on repeated airtimereplenishment. By permitting a balance-independent SIM card to beserviced independently from a prepaid SIM card, as disclosed, maypreserve a prepaid insufficient credit announcement to prompt a prepaidcaller to replenish their account.

Such a parallel circuitry embodiment is further described in greaterdetail blow with respect to FIG. 5. FIG. 5 depicts a servicearchitecture permitting a balance-independent SIM card and existingprepaid SIM card to be registered together and yet serviced separately.While the architecture depicts a single HLR and optionally multiplegsmSCF nodes, multiple HLRs and a single gsmSCF may be utilized. The SIMsubscriber data stored in the HLR, rather than the HLR and the gsmSCFitself, may enable Star SIM calls to invoke the zero charge controllingservice logic as described herein.

Thus, term “circuitry” herein is to be interpreted in a broader logicalcontext of communication paths (such as communication path 802 of a zerocharge telephony protocol system 800 described in greater detail furtherbelow) rather than narrower physical context (e.g., of analog design andphysical wires) and may incorporate wired and/or wirelesscommunications. In an embodiment, a single intelligent controller mayservice both the balance-independent (e.g, star) SIM card and thebalance-dependent (e.g., prepaid) SIM card and associated subscriberswhile isolating balance-independent SIM card control from prepaid SIMcard control.

In embodiments herein, SIM cards may be provided on a cellular network,and the HLR may be populated with the associated subscriber data.Further, Intelligent Networks (IN), such as CAMEL and O-CSI data modelsmay be utilized. CSI contents may include gsmSCF Address, Service Key(SK) and Default Call Handling indicator. The gsmSCF is used to identifythe CSE (CAMEL Service Environment) to be used for service interaction.The Service Key is a reference to the subscriber Operator SpecificService (OSS), which is used to identify the service logic to be invokedat the gsmSCF. Thus, the SK is used to address the desired Service LogicProgram Instance (SLPI) within the gsmSCF. Each Service Key may alsohave an associated default call handling indicator.

Default call handling may specify the default call treatment (e.g.,RELEASE, CONNECT, CONTINUE) under certain conditions. In one embodiment,the default call handling performs the Service Logic as disclosed, wherethe mobile address of user B is modified to include the routing prefixfollowed by a CONNECT command to permit the network to invoke thedisclosed flash signaling as the default call handling procedure. Suchflash signaling permits a call to be serviced under certain conditions(e.g., call gapping during high call volume) rather than failing toservice a call.

SIM cards may have associated subscription information stored togetherwith SIM authentication data, such as International Mobile SubscriberIdentity (IMSI) and Secret key (value Ki) used by the GSM A3A8 Comp128authentication algorithms. The architecture in FIG. 5 focuses on the INcontroller node network address and associated Service Keys assigned tocontrol the originating call setup Service Logic described herein.

SIM blocks may describe a range of contiguous IMSI that may be easilyallocated with the same subscription profile in an HLR. It iscontemplated by and within the scope of this disclosure that physicalSIM cards, electronic SIM cards (eSIM), or combinations thereof may beutilized. SIM subscription information may be populated into the HLR bymethods understood to those of skill in the art, such as the networkaddress of an originating Intelligent Network Service Control Point,Service Keys and Trigger Detection Points.

The SIM block of the balance-independent SIM card may be provisionedwith an alternate IN node address, or the same node address and adifferent Service Key, stored in the HLR O-CSI (Originating CamelSubscription Information) data, which is downloaded to the servicingMSC/VLR. Such data binds all originating calls from thebalance-independent SIM card to the assigned Control Function andService Logic Program Instance (SLPI), per the CAMEL MSC/gsmSSF callsetup control and, similarly, per IN INITDP and associated MSC/SCP MAPdialogs.

Shunting the balance-independent SIM card associated call setups awayfrom a primary prepaid IN node, or invoking a Star SLPI on the prepaidnode using a distinct Service Key stored in the HLR subscription record,permits escaping and bypassing billing and associated billing nodes.Such a billing bypass function forgoes a credit verification toautomatically, directly, and universally modify the called party addresswith a prefix that routes the call to the Star Switch on issuing CONNECTwith modified arguments (e.g., a modified mobile destination address,incorporating a routing prefix to the called party number).

Hence, while a call that has sufficient credit may be commanded by an INnode to CONTINUE unmodified, on detecting insufficient credit, the INnode may continue on to modify the called address to include a routingprefix to the Star Switch and issue a CONNECT command (rather than aDISCONNECT, REJECT, AUTHORIZATION FAIL, RELEASE or similar IN command),commanding the MSC to continue with the call on the now modified addressprefix. The MSC then reroutes the prefixed call, on a routing entrylookup and automated translation using the customized connection logicdescribed herein, to direct the call to the Star Switch 305, 335 forsignaling per the disclosed methods.

Referring to FIG. 5, as described above, a parallel architectureutilizing and provisioning the prepaid SIM card and thebalance-independent (e.g., star) SIM card of the dual SIM card system ofFIG. 1A and of FIG. 1B is shown. While some embodiments may have anallocation to physical nodes different from that shown, the physicalseparation of the logic shown does not affect the modelling disclosed.Thus, the Star gsmSCF is circled with a dotted rather than a solid lineto indicate logical rather than physical entity separation. The prepaidSIM card and the balance-independent SIM card may have the same CSIgsmSCF addresses with distinct Service Keys, SK1 and SK0, whichrespectively invoke a different service logic.

A prepaid SIM card parallel architecture is shown on the left side ofFIG. 5. In flow item 500, a plurality of existing prepaid SIM cards areprovisioned with O-CSI data including a gsmSCF node address X (gsmSCF-X)and Service Key 1 (SK-1). A Prepaid Service Key value equal to “1” ismerely illustrative and may be any suitable value. In flow item 501, thePrepaid SIM O-CSI subscription data is stored in an HLR and ispropagated towards the servicing MSC/gsmSSF on SIM registration andattachment to the network.

In flow item 502, the user A associated with the prepaid SIM card usesthe associated first user mobile device 300, 330 to dial the mobileaddress of the second user mobile device 308, 338 of user B. In flowitem 503, the MSC/gsmSSF BCSM encounters the INITDP, and in flow item504, the CAMEL MSC/gsmSSF initiates a dialog with service controlfunction gsmSCF-X using Camel Service Key SK-1 to invoke the PrepaidLogic. Both gsmSSF and gsmSCF, while they may be physically distinct,are depicted as a single node with respect to flow item 504, though theymay be independent nodes.

In flow item 505, a credit verification queries the current balance inan account associated with A. In flow item 506, if account A isdetermined to have insufficient credit to complete the call, the networkplays a service announcement to the first user mobile device 300, 330associated with account A of caller A (e.g., user A). This service mayannounce in flow item 507 that insufficient credit is available tocomplete the call, (e.g., “You have insufficient credit to complete thecall”), and in flow item 508, the caller A is disconnected, and theconnection is complete. However, in the alternative embodiments, ratherthan rejecting or disconnecting the call, rather than disconnecting thecaller, the user may be presented with service options (e.g., an IVRmenu), for example, to replenish their credit by purchasing additionalairtime, requesting airtime credit, and/or or permitting the caller torequest a collect call. In one embodiment, a CAMEL Specialized ResourceFunction (SRF), interlaces such an IVR menu into the call, by playing anassociated announcement enumerating the service options, for example,announcing “Press 1 for Option one, Press 2 for Option two . . . ” etc.,and then performing digit collection (DTMF) to capture any user Aselection(s).

In flow item 509, if account A is determined to have sufficient creditto complete the call, gsmSCF commands the MSC/gsmSSF to continue thecall to the second user mobile device B. In flow item 510, if the seconduser mobile device B is available the call matures to ringing statepermitting the recipient to answer.

On the right side, FIG. 5 depicts a parallel architecture for abalance-independent SIM card system. In flow item 550, a plurality ofbalance-independent SIM cards are provisioned with CSI data includinggsmSCF node address X (gsmSCF-X) and Service Key 0 (SK-0). A zerobalance Service Key value equal to “0” is merely illustrative and may beany suitable value. In flow item 551, associated STAR SIM O-CSIsubscription data is stored in an HLR and is propagated towards theservicing MSC/gsmSSF on SIM attachment to the network.

In flow item 552, the user A associated with the balance-independent SIMcard uses the associated first user mobile device 300, 308 to dial themobile address of the second user mobile device 330, 338 of user B. Inflow item 553, the MSC/gsmSSF BCSM encounters the INITDP, and in flowitem 554, the CAMEL MSC/gsmSSF initiates a dialog with service controlfunction gsmSCF-X using the Camel Service Key SK-0 to invoke the STARLogic (e.g., zero balance connect through routing prefix modification).Both gsmSSF and gsmSCF, while may be physically distinct, are depictedas a single node in flow item 554, similar to the node in flow item 504,while now executing a different service logic.

In flow item 555, as described herein, credit verification is shortcircuited and not necessary for the balance-independent SIM card whilebypassing communication with billing nodes. The gsmSCF modifies the Baddress with a routing prefix that addresses a Star Switch 305, 335 andcommands the MSC/gsmSSF to connect the call using the modified addresswith the routing prefix as described herein.

In flow item 556, the Star Switch 305, 335 plays a ring-back-tone (RBT)to the first user mobile device 300, 330 of user A. Momentarilythereafter, in flow item 557, the caller (e.g., user A) is disconnectedand the first connection is complete. Embodiments of the differentservice logic of flow item 504 to place the call to user B from the StarSwitch 305, 335 is described in greater detail below with respect toFIGS. 6A-6B along with describing the dependencies between the HLR, SIM,CSI and SLPI in reference to FIGS. 6A-6B that present respective logicalintelligent network views. FIG. 6C illustrates an embodiment of a quotabased synchronous zero cost scheme, which is described in greater detailfurther below.

IN supports programmable service logic. An IN node, service controlpoint (SCP) or service control function (SCF) can remotely command andcontrol a Mobile Switch (MSC) at well-defined Points In Call (PIC) andtrigger detection points (TDPs) encountered in the Basic Call StateModel (BCSM). CAMEL is an IN protocol as known to those of ordinaryskill in the art. As the CAMEL O-CSI is subscriber specific, differentsubscribers may subscribe to different CAMEL services. CAMEL is also anextensible platform that can host different service logic, for differentsubscribers and at different PICs, supporting different OperatorSpecific Services (OSS) on the same node. CAMEL permits remote SLPIinvocation at the INITDP using Service Keys assigned to the SIM, and themethods and systems disclosed herein may leverage this CAMEL feature tohost two mass market segments, prepaid users who have prepaid funds forairtime and/or zero balance users not providing any funds for airtime,on the same networking infrastructure. It is contemplated by and withinthe scope of this disclosure that such zero charge systems may beutilized in conjunction with post-paid accounts as well that are billedin a periodic cycle, such as where an account may be deactivated due tonon-payment. INITDP may be invoked at a Detection Point 2 (e.g., DP2Collected Information), where the O-CSI has been analyzed.

Intelligent Service switching logic invoked on CAMEL Service Keys maypermit the balance-independent SIM cards as described herein to behosted on the same platform yet serviced independently. A distinctService Key assigned to the balance-independent SIM card is configuredto invoke the associated SLPI implementing the disclosed billing shortcircuit, address modification, and CONNECT call handling algorithm. Forexample, where P is Prepaid, and S is Star (e.g., zero balance), theservice logic may follow: (1) PSIM>gsmSCF-X+SK-1 INITDP=>P Service LogicSLPI-1; and (2) S SIM>gsmSCF-X+SK-0 INITDP=>S Service Logic SLPI-0.

Service collocation delivers important efficiencies and cost benefits tothe operator. The same infrastructure can be utilized for servicing bothan existing positive balance (prepaid) and a zero balance base withouteither impairing or encroaching on the other. Alternatively, gsmSCF-Xmay be physically distinct nodes, with addresses gsmSCF-1 and gsmSCF-0,rather than the same physical entity to completely isolate the serviceand the circuitry, in what may be described as a Network Abstractionsuitable for a Mobile Virtual Network Operator (MVNO).

Referring to FIG. 6A, a unified logic model of prepaid and zero chargeservice key logic for the methods of FIGS. 1A and 2 is shown. Withreference to FIG. 6A which describes a unified prepaid and zero callermodel, in flow item 600, the HLR stores subscriber profiles of positivebalance or credit (prepaid) SIM cards. In flow item 601, the prepaid SIMcards are each associated with an account that stores a current airtimebalance. In flow item 602, a prepaid SIM card has associated O-CSI data,which includes the gsmSCF address (gsmSCF-X) and INITDP Service Key(SK-1). While multiple service keys may be defined, controlling distinctservice logic at different PICs, the illustrated embodiment shows asingle SK applied to the INITDP DP Collected Information. In flow item603, when a prepaid call is requested by a caller (e.g., user A), theMSC/gsmSSF enters the O-BCSM. On encountering the INITDP (DP2), theMSC/gsmSSF requests call control from gsmSCF-X (640), with SK-1. Thisinvokes the Prepaid Service Logic Program Instance SLPI-1, whichexecutes the illustrated conditional statement commanding the MSC asfollows: (1) if the account associated with the caller A dialing anaddress of user B has insufficient balance or credit to complete thecall; (2) then connect on a modified address of user B incorporating astar routing prefix to place the call to user B via the asynchronousswitching node as disclosed; (3) else continue using the prepaid SIMcard with sufficient balance or credit to complete the call to user B.

Such conditional logic is able to highlight a prepaid SLPI incorporatingthe disclosed script for zero balance prepaid calls to deliver a unifiedprepaid and prepaid zero balance controller to place calls even with azero balance determination.

Referring to FIG. 6B, a parallel logic model for prepaid and star zerocharge service key logics for the methods of FIG. 1B and FIG. 2 isshown. FIG. 6B describes a collocated yet parallel switched prepaid andstar zero caller model. In flow item 630, the HLR is configured to storeboth prepaid and star (zero balance) SIM subscriber profiles. In flowitem 631, the prepaid SIM cards have an account which stores a currentairtime balance. In flow item 632, the prepaid SIM card has associatedO-CSI data, which includes the gsmSCF address (gsmSCF-X) and INITDPService Key (SK-1). While multiple service keys may be defined,controlling distinct service logic at different PICs, the illustratedexample shows a single SK applied to the INITDP (e.g., DP2 CollectedInformation).

In flow item 633, when a prepaid call is requested by user A attemptingto call a mobile address associated with user B, the MSC/gsmSSF entersthe O-BCSM. On encountering the INITDP, the MSC/gsmSSF requests callcontrol from gsmSCF-X in flow item 640 with SK-1. This invokes thePrepaid Service Logic Program Instance SLPI-1, which executes theillustrated conditional statement commanding the MSC as follows: (1) ifthe account associated with the caller A (e.g., user A) has insufficientbalance or credit to complete the call; (2) then announce insufficientbalance or credit to user A; (3) else continue the call. Suchconditional logic preserves Prepaid Service Logic SLPI-1, or otherprepaid logic that may apply and is contemplated herein, for zerobalance callers.

In flow item 641, the balance-independent SIM cards may perpetually beon zero balance. All outgoing calls from the balance-independent SIMcard may be switched as per the disclosed signaling protocol to connect,the calls do not require billing verification during call setup asdescribed herein. In flow item 642, the balance-independent SIM has anassociated O-CSI record, which includes the gsmSCF address (gsmSCF-X)and associated INITDP (DP2 Collected Information) Service Key (SK-0). Aswith the prepaid SIM card described herein, multiple service keys may bedefined, controlling service logic at different PICs, while theillustrated example shows a single SK applied to the DP.

In flow item 643, when a Star call is requested, the MSC/gsmSSF entersthe O-BCSM. On encountering DP2 the MSC/gsmSSF requests call controlfrom gsmSCF-X in flow item 640 with SK-0. This invokes the Star ServiceLogic Program Instance SLPI-0 which, as illustrated, executes theCONNECT command on the modified B address, incorporating a routingprefix addressing the Star Switch 305, 335. It is contemplated by andwithin the scope of this disclosure that other service logicincorporating the customized connection logic herein may be applied.

In describing an alternate Service Logic Instance with reference to FIG.6C, a natively signaled flash communications embodiment forgoes the needto loop the call setup via a bespoke asynchronous Star Switching node.In this synchronous signaling embodiment, the disclosed methods executealong the native originating and terminating ISUP call setup path.

In such a native Star Service Logic embodiment, on supporting INplatforms, such as CAMEL Phase 4, the balance-independent SIM card isconfigured to assign an additional Service Key SK-180 to the EDP-R forservicing the O_Term_Seized (O_Alerting) trigger detection point. Inflow item 660, the HLR is configured to store prepaid SIM cardsubscriber profiles. In flow item 661, the prepaid SIM cards each havean account which stores a respective current airtime balance. In flowitem 662, each prepaid SIM card has an associated O-CSI record, whichincludes the gsmSCF address (gsmSCF-X) and associated INITDP (DP2Collected Info) Service Key (SK-1). The O-CSI furthermore has a secondService Key (SK-180) associated with Trigger Detection PointO_Term_Seized (O_Alerting).

In flow item 663, when a prepaid call is requested by user A attemptingto dial a mobile address of user B, the MSC/gsmSSF enters the O-BCSM. Onencountering the INITDP, the MSC/gsmSSF requests call control fromgsmSCF-X in flow item 680 with SK-1. This invokes the Prepaid ServiceLogic Program Instance SLPI-1, which executes the illustratedconditional statement. The associated conditional logic invokes analgorithm to deliver a disclosed flash ring signaling protocol excludingthe bespoke Star Switch 305, 335 such that the star address prefix is nolonger required.

As a non-limiting example, on encountering the INITDP and invoking theSLPI-1 service logic with associated SK-1, the gsmSCF executes aconditional statement that may be summarized as follows: (1) if user Ahas insufficient credit; (2) then begin (2a) RRBE (OTS), (2b) ACH(0SEC); (3) end; and (4) CONTINUE processing the call.

With respect to the RRBE (OTS) short hand notation, SLPI-1 requests andarms event reports on the BCSM, as a Request Report BCSM Event (RRBE),in particular, arming the O_Term_Seized (OTS) or O_Alerting DetectionPoint, as an EDP-R (Event Detection Point Request) so that the call ispaused and the MSC requests instruction on encountering the DetectionPoint. On triggering, the EDP invokes SLPI-180 where the gsmSCFinstructs the MSC to release the call as the second user mobile deviceof user B has been alerted through presenting a missed call at thesecond user mobile device as the destination device. By programmaticallyarming this alerting EDP for callers with insufficient credit, thecontroller can selectively disconnect ringing state for zero balancecallers alone, without impacting callers with sufficient credit, whichcalls can ring indiscriminately until answered.

With respect to the ACH (0SEC) short hand notation, since thebalance-independent SIM card has zero airtime credit, the gsmSCF AppliesCharging (ACH) with a Maximum Call Duration Quota set to zero seconds(e.g., CAMEL maxCallPeriodDuration=0) and instructs the MSC to releasethe call when the quota is exceeded (releaseIfdurationExceeded=True).Such Zero Quota Release configuration instructs the MSC/gsmSSF toterminate the call on encountering a charge event, such as ANSWER, sincethe zero quota does not sustain a charge.

The quota is thus set to intentionally and instantly expire and exhaustthe call at a charging onset, permitting the call to mature to ringing(e.g., signaling) while simultaneously preventing the call fromprogressing to speech (e.g., answering) that would otherwise incur acharge. In the latter instance, since the quota is zero, the MSC/gsmSSFis configured to instantly disconnect a connected call. The quota mayalso be set to any increment, e.g., zero to one seconds, for similareffect (e.g., 100 ms).

With regard to the CONTINUE command, the gsmSCF progresses to commandthe MSC/gsmSSF to CONTINUE with the call, thus permitting the call tocontinue even though it is set for instant disconnection on ringingdetection or on answering.

With regard to a RELEASE command, on the MSC/gsmSSF receiving Alertingindication that the B device is ringing (ISUP ACM/CPG Alerting), theO-BCSM leads to the O_Term_Seized DP. Such action triggers theEDP-Request with assigned SK-180, where the gsmSSF suspends callprocessing awaiting instruction from the gsmSCF. SLPI-180, whichservices the EDP-R, commands the gsmSSF to RELEASE the call(CAP_Release_Call), thereby terminating the connection and completingthe Downlink Flash Communication.

A distinction from FIGS. 6A and 6B in the natively signaled embodimentof FIG. 6C is that caller A remains on the line until such time as theremote party is alerted or on encountering another network condition(e.g., Network/User Busy). As such, this natively signaled embodimentpresents a quasi-flash communications protocol since RBT presentation isbased on synchronous signaling to the far end destination second usermobile device of user B. The Uplink communication is therefore coupledin the natively signaled embodiment to the Downlink communication, andconsequently the signaling protocol has a longer Call Holding Time (CHT)than the protocols of FIGS. 6A and 6B. However, the synchronoussignaling embodiment of FIG. 6C is configured to deliver a realtimeringing, and other network tones (e.g., user and network busy) andnotifications to user A, along the natively switched call path, withoutlooping the call setup and control via the disclosed Star Switch asrequired for FIGS. 6A and 6B. This distinction permits the gsmSCF tocontrol and implement the disclosed Flash Communications Protocolnatively, along a synchronous call path, without requiring a bespokeswitching and signaling node (e.g., the Star Switch 305, 335).

The balance-independent SIM card described herein may have basicservices provisioned, such as an ability to make outgoing (Originating)calls that are then switched and serviced per the flash signalingembodiments disclosed herein. While other services may be provisioned,these SIM cards may have a minimum number of features enabled. As anon-limiting example, voicemail services may be excluded asbalance-independent SIM users expectantly await return calls,precipitated by the flash ring protocol, and as such would not require avoicemail feature.

Referring to FIG. 7, an asymmetrical zero charge SIM card CLI provisionis shown. Asymmetrical CLI is a feature configured to counterintuitivelydisable Calling Line Identity Presentation (CLIP) for thebalance-independent SIM cards disclosed herein to intentionally mask whois calling back. As the balance-independent SIM card is predicated onreverse ringing, where a user pings another user for callback to reversecall charges to the other user upon callback, the system may beconfigured to permit these users to ping only those users (e.g., PINGuser to signal caller identity) who have prepaid and postpaid accounts,and who are thus able to return and pay for a call.

CLIP is a supplementary network feature that permits recipients toidentify callers based on calling line identity. By disabling CLIP onbalance-independent SIM cards in embodiments, and presenting allincoming calls as UNKNOWN, the zero charge systems herein prevents usersfrom flashing each other, without placing any speech callbacks toconvert pings to revenue generating callbacks. Notwithstanding the factthat disabling CLIP results in all incoming calls displaying UNKNOWN,such incoming calls may be highly anticipated and awaited and thusanswered.

In flow item 700, a prepaid and postpaid SIM card user C may have CLIPenabled by default. In flow item 710, a balance-independent SIM carduser A may have CLIP disabled, and in flow item 720 abalance-independent SIM card user B may have CLIP disabled. In flow item730, the system determines if an identity matrix is showing when CLI ispresented (Y/ES) and when it is suppressed (N/O) between a first userand a second user. For example, a call between user A and user C doesnot suppress the CLIP such that CLIP is enabled (A2C Y) while a callbetween user A and user B does suppress the CLIP such that CLIP isdisabled (A2B N). Given such CLIP provisioning, balance-independent SIMcard users A and B may transmit their calling identity when placingcalls while not receiving a calling identity when receiving calls.

In embodiments, CLIP disabled (e.g., having CLI suppressed for incomingcalls), together with no voicemail provision, may ensure that the zerobalance user base cannot screen and divert calls without the networkcollecting revenue from at least one user. In embodiments, ifbalance-independent SIM user A wishes to have CLIP enabled, the user Amay be required to pay an activation fee.

The systems and methods disclosed herein may service both prepaid userswith zero airtime as well as new balance-independent SIM users who wishto place calls without any required prepaid or postpaid balance with thesame flash signaling protocol. Prepaid systems are predicated on acyclical topup, requiring users to purchase airtime when their balanceis depleted. By isolating the balance-independent SIM call servicecontrol, either by assigning a new IN node to the SIM subscription or byassigning a new Service Key that invokes the Star SLPI logic, theprepaid option may remain intact and work in parallel to thebalance-independent systems described herein.

Thus, balance-independent SIM card calls may be serviced and controlledindependently from prepaid calls as described herein. Such a circuitisolating architecture permits the new zero balanced base oftelecommunication users to be serviced according to the disclosed flashsignaling methods without limiting option and further providingalternative options to a prepaid user base to place a call even withinsufficient balance or credit.

In an embodiment, dialing a USSD service code (e.g., *123*#) can migratea balance-independent SIM card to a prepaid SIM card to permit users toadd credit to their account in order to pay for their own communication.In yet another embodiment, the balance-independent SIM can beautomatically upgraded to a prepaid SIM card on receiving airtimetransferred from another prepaid SIM card. Similarly, such an upgradedSIM can be automatically migrated back to a balance-independent SIM oncesuch gifted airtime is depleted. In one such SIM migration, thebalance-independent SIM Service Key (SK0) stored in the HLR CSI may bechanged to the Prepaid Service Key (SK1), thereby invoking the prepaidrather than the balance-independent SLPI. In an alternate embodiment,where the controlling nodes are physically distinct, the gsmSCF addressmay be changed from balance-independent gsmSCF-0 to prepaid gsmSCF-1.

In another embodiment, a symbolic routing prefix such as the star symbol(*) addresses an internet hosted SIP Signaling Node, and any prefix thatroutes to any signaling node that commands control over the call setupprocess and progress may be utilized and is in the scope of thisdisclosure, including without limitation, an internal routing prefix andan SS7/ISUP signaling or switching node. In such an ISUP signalingembodiment, the disclosed originating and terminating flash ringprotocols may be readily translated from SIP to ISUP as illustrated anddisclosed herein.

Further, while embodiments described herein disclose ringing adestination device to deposit an originating calling line identity,other bearers and protocols may similarly ping and notify the calledparty on the Downlink communication. Alternate signaling embodiments mayinclude, without limitation, pinging via Short Messaging Service (SMS),Multimedia Messaging Service (MMS), and/or Rich Communication Systems(RCS) messaging systems and/or via Internet messaging systemsaddressable on a telephone number (e.g., pinging via an applicationprogramming interface (API) to popular applications such as WhatsApp),and/or pinging via a Unstructured Supplementary Services Data (USSD)push and other data bearing protocols. Any discrete communication thatcan deliver user A information to the user B may be utilized.

While signaling the called party (e.g., user B) using a FLASH ringmethod is disclosed to momentarily ring and disconnect, the disclosedsystems and methods are further configured to seamlessly hook abalance-independent (e.g., zero balance) call during the originationphase by modifying the called number with a routing prefix directing thecall towards the switching node (e.g., Star Switch 305, 335) forprocessing. Consequently, any other originating or terminating protocolother than flash ringing utilizing the modification scheme may besimilarly implemented.

Referring to FIG. 8, a zero charge telephony protocol system 800 forimplementing a computer and software-based method to implement the zerocharge SIM card protocols described herein is illustrated. The zerocharge telephony protocol system 800 may be implemented along with usinga graphical user interface (GUI) that is accessible at a mobile clientdevice (e.g., a first user mobile device 820 and a second user mobiledevice 824), for example. The mobile client device may be a smart mobiledevice, which may be a smartphone, a tablet, or a like portable handheldsmart device. The machine readable instructions may cause the zerocharge telephony protocol system 800 to, when executed by the processor,interact with one or more SIM cards associated with the mobile clientdevice of the user as described herein. The machine readableinstructions may cause the zero charge telephony protocol system 800 to,when executed by the processor, interact with the one or more SIM cardsto follow one or more control schemes as set forth in the one or moreprocesses described herein.

The zero charge telephony protocol system 800 includes machine readableinstructions stored in non-transitory memory that cause the zero chargetelephony protocol system 800 to perform one or more of instructionswhen executed by the one or more processors, as described in greaterdetail below. The zero charge telephony protocol system 800 includes acommunication path 802, one or more processors 804, a memory 806, aswitch component 812 that may be asynchronous or synchronous, a storageor database 814, at least one SIM component 816, a network interfacehardware 818, a first user mobile device 820, a network 822, and asecond user mobile device 824. The various components of the zero chargetelephony protocol system 800 and the interaction thereof will bedescribed in detail below.

In some embodiments, the zero charge telephony protocol system 800 isimplemented using a wide area network (WAN) or network 822, such as anintranet or the Internet, or other wired or wireless communicationnetwork that may include a cloud computing-based network configuration.The mobile client devices 820, 824 may include digital systems and otherdevices permitting connection to and navigation of the network, such asthe smart mobile device. Other zero charge telephony protocol system 800variations allowing for communication between various geographicallydiverse components are possible. The lines depicted in FIG. 8 indicatecommunication rather than physical connections between the variouscomponents.

As noted above, the zero charge telephony protocol system 800 includesthe communication path 802. The communication path 802 may be formedfrom any medium that is capable of transmitting a signal such as, forexample, conductive wires, conductive traces, optical waveguides, or thelike, or from a combination of mediums capable of transmitting signals.The communication path 802 communicatively couples the variouscomponents of the zero charge telephony protocol system 800. As usedherein, the term “communicatively coupled” means that coupled componentsare capable of exchanging data signals with one another such as, forexample, electrical signals via conductive medium, electromagneticsignals via air, optical signals via optical waveguides, and the like.

As noted above, the zero charge telephony protocol system 800 includesthe processor 804. The processor 804 can be any device capable ofexecuting machine readable instructions. Accordingly, the processor 804may be a controller, an integrated circuit, a microchip, a computer, orany other computing device. The processor 804 is communicatively coupledto the other components of the zero charge telephony protocol system 800by the communication path 802. Accordingly, the communication path 802may communicatively couple any number of processors with one another,and allow the modules coupled to the communication path 802 to operatein a distributed computing environment. Specifically, each of themodules can operate as a node that may send and/or receive data. Theprocessor 804 may process the input signals received from the systemmodules and/or extract information from such signals.

As noted above, the zero charge telephony protocol system 800 includesthe memory 806, which is coupled to the communication path 802, andcommunicatively coupled to the processor 804. The memory 806 may be anon-transitory computer readable medium or non-transitory computerreadable memory and may be configured as a nonvolatile computer readablemedium. The memory 806 may comprise RAM, ROM, flash memories, harddrives, or any device capable of storing machine readable instructionssuch that the machine readable instructions can be accessed and executedby the processor 804. The machine readable instructions may compriselogic or algorithm(s) written in any programming language such as, forexample, machine language that may be directly executed by theprocessor, or assembly language, object-oriented programming (OOP),scripting languages, microcode, etc., that may be compiled or assembledinto machine readable instructions and stored on the memory 806.Alternatively, the machine readable instructions may be written in ahardware description language (HDL), such as logic implemented viaeither a field-programmable gate array (FPGA) configuration or anapplication-specific integrated circuit (ASIC), or their equivalents.Accordingly, the methods described herein may be implemented in anycomputer programming language, as pre-programmed hardware elements, oras a combination of hardware and software components. In embodiments,the zero charge telephony protocol system 800 may include the processor804 communicatively coupled to the memory 806 that stores instructionsthat, when executed by the processor 804, cause the processor to performone or more functions as described herein.

Still referring to FIG. 8, as noted above, the zero charge telephonyprotocol system 800 may comprise the display such as a GUI on arespective screen of the mobile client devices 820, 824 for providingvisual output and/or receiving input such as a dialed number on atouchscreen interface. The mobile client devices 820, 824 may includeone or more computing devices across platforms, or may becommunicatively coupled to devices across platforms, such as smartmobile devices including smartphones, tablets, laptops, and the like.The display on the screen of the mobile client devices 820, 824 iscoupled to the communication path 802 and communicatively coupled to theprocessor 804. Accordingly, the communication path 802 communicativelycouples the display to other modules of the zero charge telephonyprotocol system 800. The display can include any medium capable oftransmitting an optical output such as, for example, a cathode ray tube,light emitting diodes, a liquid crystal display, a plasma display, orthe like. Additionally, it is noted that the display or the mobileclient devices 820, 824 can be communicatively coupled to at least oneof the processor 804 and the memory 806. While the zero charge telephonyprotocol system 800 is illustrated as a single, integrated system inFIG. 8, in other embodiments, the systems can be independent systemsand/or sub-systems.

The zero charge telephony protocol system 800 may comprise: (i) theswitch component 812, which may be asynchronous as the Star Switch 305,335 as described herein and (ii) the at least one SIM component 816,which may be a prepaid SIM card and/or a balance-independent SIM card asdescribed herein. The at least one SIM component 816 may at least onesubscriber identity module (SIM) card, which comprises an integratedcircuit that securely stores an international mobile subscriber identity(IMSI) number and related key information used to identify andauthenticate subscribers of smart mobile telephony devices. Each SIMcard may also store contact information and its own unique serial numberas an integrated circuit card identifier (ICCID), the IMSI number,security authentication and ciphering information, local network relatedtemporary information, a list of accessible user services, a userpassword as a personal identification number (PIN), and a personalunblocking code to unlock the PIN. A card services provider may be ableto identify and authenticate a SIM card to provide services, such ascellular and/or wireless data services to a device within which the SIMcard is installed. The switch component 812 and the at least one SIMcomponent 816 are coupled to the communication path 802 andcommunicatively coupled to the processor 804. The processor 804 mayprocess the input signals received from the system modules and/orextract information from such signals.

Data stored and manipulated in the zero charge telephony protocol system800 as described herein may be used to leverage a cloud computing-basednetwork configuration such as the Cloud (e.g., a cloud server in a cloudnetwork configuration utilizing cloud computing). The zero chargetelephony protocol system 800 includes the network interface hardware818 for communicatively coupling the zero charge telephony protocolsystem 800 with a computer network such as network 822, which maycomprise the Cloud. The network interface hardware 818 is coupled to thecommunication path 802 such that the communication path 802communicatively couples the network interface hardware 818 to othermodules of the zero charge telephony protocol system 800. The networkinterface hardware 818 can be any device capable of transmitting and/orreceiving data via a wireless network. Accordingly, the networkinterface hardware 818 can include a communication transceiver forsending and/or receiving data according to any wireless communicationstandard. For example, the network interface hardware 818 can include achipset (e.g., antenna, processors, machine readable instructions, etc.)to communicate over wired and/or wireless computer networks such as, forexample, wireless fidelity (Wi-Fi), WiMax, Bluetooth, IrDA, WirelessUSB, Z-Wave, ZigBee, or the like.

Still referring to FIG. 8, data from various applications running onmobile client devices 820, 824, including data associated with the atleast one SIM component 816 communicatively coupled to the mobile clientdevices 820, 824, can be provided to the zero charge telephony protocolsystem 800 via the network interface hardware 818. The mobile clientdevices 820, 824 can be any device having hardware (e.g., chipsets,processors, memory, etc.) for communicatively coupling with the networkinterface hardware 818 and a network 822. Specifically, the mobileclient device 820, 824 can include an input device having an antenna forcommunicating over one or more of the wireless computer networksdescribed above.

The network 822 can include any wired and/or wireless network such as,for example, wide area networks, metropolitan area networks, theInternet, an Intranet, the Cloud, satellite networks, or the like.Accordingly, the network 822 can be utilized as a wireless access pointby the mobile client devices 820, 824 to access one or more servers(e.g., of the Cloud). Accessed servers, such as a cloud server,generally include processors, memory, and chipset for deliveringresources via the network 822. Resources can include providing, forexample, processing, storage, software, and information from the one ormore servers to the zero charge telephony protocol system 800 via thenetwork 822. Additionally, it is noted that the one or more servers canshare resources with one another over the network 822 such as, forexample, via the wired portion of the network 822, the wireless portionof the network 822, or combinations thereof.

In one embodiment, a zero charge telephony protocol system 800 andassociated methods may include one or more processors 804, anon-transitory memory 806 communicatively coupled to the one or moreprocessors 804, and machine readable instructions. The machine readableinstructions are stored in the non-transitory memory 806 and cause thesystem 800 to automatically perform protocols when executed by the oneor more processors 804, such as at least the following to: receive froma first user mobile device 820 (e.g., device 300, 330 and flow items310, 340 as shown in FIGS. 3A-3B and flow items 110, 110 of FIGS. 1A-1B)associated with a first user account a call signal indicative of arequest to place and complete a call to a mobile address of a seconduser mobile device 824 (e.g., device 308, 338 and flow items 311, 341 ofFIGS. 3A-3B); and automatically modify the mobile address with a routingprefix to generate a modified call signal indicative of a modifiedaddress including the routing prefix when the first user account hasinsufficient balance to complete the call or is independent of balance(as shown in flow 101-102 of FIG. 1A, flow item 112 of FIG. 1B, and flowitems 312, 342 of FIGS. 3A-3B).

The machine readable instructions may further cause the system 800 toperform at least the following when executed by the one or moreprocessors: route to an asynchronous signaling switch based on a trunkcommunication path associated with the modified address (as shown inflow item 137 of FIG. 1C and flow items 313, 343 of FIGS. 3A-3B); revertthe modified call signal at the asynchronous signaling switch to thecall signal; deliver the call signal from the asynchronous signalingswitch to the second user mobile device 824 (FIGS. 2, 3A, 3B, and 8) tocomplete the call; and automatically disconnect the call from the seconduser mobile device 824 immediately upon receipt of the call signal bythe second user mobile device (flow items 280-290 of FIG. 2 and device308, 338 and flow items 320-323, 350-353 of FIGS. 3A-3B). As describedherein, immediately may reference an immediate or substantiallyimmediate period of a short duration to prevent answering of the callafter call completion (e.g., call ringing at an input destination) thatoccurs on the basis of placing (e.g., initiating and routing) the calland any associated verbal/speech communication over the call that mayonset charges associated with the call.

The request may be received from the first user mobile device 300, 330,820 (FIGS. 3A-3B and 8) at a MSC 301, 331 (flow items 310, 340 of FIGS.3A-3B) to place and complete the call to the mobile address of thesecond user mobile device 308, 338, 824. Further, the mobile address maybe automatically modified with a routing prefix including a star symbol(*) to generate the modified call signal indicative of the modifiedaddress including the star symbol as the routing prefix when the firstuser account has insufficient balance to complete the call.

The MSC 301, 331 may lookup a pre-configured routing table including atrunk indicator of the trunk (e.g., trunk communication path) associatedwith the modified address and translate/route the modified address basedon the trunk indicator of the trunk associated with the modified addressfrom the pre-configured routing table (e.g., flow item 136 of FIG. 1Cand flow items 313, 343 of FIGS. 3A-3B). The modified call signal may beautomatically routed along the trunk from the MSC to a Gateway MSC(GMSC) and then automatically routed along the trunk from the GMSC tothe asynchronous signaling switch as the switch component 812 (e.g.,flow items 137-140 of FIG. 1C and flow items 313, 343 of FIGS. 3A-3B).

In embodiments, the call may be disconnected from the first user mobiledevice by the asynchronous signaling switch (e.g., the switch component812 of FIG. 8 and/or Star Switch 305, 335 and flow items 316, 346 ofFIGS. 3A-3B) when the first user account has insufficient balance tocomplete the call in concurrence to routing the call signal to thesecond user mobile device. The call may be tracked between the firstuser mobile device 300, 330, 820, the asynchronous signaling switch 305,335, 812, and the second user mobile device 824 with a plurality of calldata recording (CDR) codes associated with the call within a period oftime (flow items 318, 348 of FIGS. 3A-3B). A second user account of thesecond user mobile device 308, 338, 824 may be charged based on theplurality of CDR codes associated with the call upon a callback from thesecond user mobile device 308, 338, 824 to the first user mobile device300, 330, 820 within the period of time.

The call signal may be delivered from the asynchronous signaling switch305, 335, 812 to the second user mobile device 308, 338, 824 along withan identification delivery (e.g., CLI) configured to identify the firstuser mobile device 300, 330, 820, a ringing permission, and an answeringrestriction. As described herein, the ringing permission is configuredto permit the second user mobile device to ring (or otherwise indicatean incoming call) upon receipt of the call signal and associatedcompletion of the call, and the answering restriction is configured torestrict the second user mobile device from answering the call toprovide access to speech communication, which may otherwise incur acharge. The call may be automatically disconnected from the second usermobile device 308, 338, 824 based on receipt by the second user mobiledevice of the identification delivery, the ringing permission, and theanswering restriction (as shown in flow items 321-323, 351-353 of FIGS.3A-3B).

In embodiments, the first user account may be associated with abalance-dependent subscriber identification module (SIM) card (e.g., aprepaid SIM card as a non-limiting example) and a balance-independentSIM card (e.g., a zero balance, zero airtime, and/or no-charge SIM cardas non-limiting examples) as the at least one SIM component 816 (asshown in FIGS. 1A, 3A, 5, 6A-6B, and 8). As shown in FIG. 6B, thebalance-dependent SIM card may be configured to include balance (e.g.,digital monetary funds representative of payment) to place and completethe call and incur a charge through a balance-dependent service keyinvoking a balance-dependent logic when the first user account hassufficient balance to complete the call. As further shown in FIG. 6B,the balance-independent SIM card may be configured to place and completethe call without charge through a balance-independent service keyinvoking a no-charge logic separate and distinct from thebalance-dependent logic when the first user account has insufficientbalance to complete the call.

Alternatively, the first user account may be associated with abalance-independent SIM card as the at least one SIM component 816 (asshown in FIGS. 1B, 3B, 5, 6B, and 8). As shown in FIGS. 1B, 3B, and 6B,the first user account associated with the balance-independent SIM cardmay be configured to place and complete the call via thebalance-independent SIM card independent of balance. In embodiments, thesystem may be configured to receive a payment in the first user account,and modify the balance-independent SIM card into a balance-dependent SIMcard having a positive balance sufficient to place and complete a call.

In one other embodiment, a zero charge telephony protocol system 800 mayinclude one or more processors 804, a non-transitory memory 806communicatively coupled to the one or more processors 804, machinereadable instructions stored in the non-transitory memory that cause thesystem 800 to perform at least the following when executed by the one ormore processors 804: receive from a first user mobile device 820 (e.g.,device 300, 330 and flow items 310, 340 as shown in FIGS. 3A-3B and flowitems 110, 110 of FIGS. 1A-1B) associated with a first user account acall signal indicative of a request to place and complete a call to amobile address of a second user mobile device 824 (e.g., device 308, 338of FIGS. 3A-3B); automatically set a call duration time quota upon asynchronous charging onset when the first user account has insufficientbalance to complete the call (e.g., flow item 663 of FIG. 6C); deliverthe call signal to the second user mobile device 308, 338 (e.g., flowitem 510 of FIG. 5) to complete the call; and automatically disconnectthe call from the second user mobile device when the call is completedand when the call duration time quota is exceeded after the synchronouscharging onset (flow item 663 of FIG. 6C). The call duration time quotamay be 0 to 1 second from the synchronous charging onset.

In embodiments, and as shown in flow items 663 and 680 of FIG. 6C, thesystem 800 (FIG. 8) may be configured to continue to place the call whenthe first user account has sufficient balance to complete the call, andpermit the call to proceed to speech post answering by the second usermobile device and based on the sufficient balance. The first useraccount may be associated with a balance-dependent subscriberidentification module (SIM) card configured to include a balance toplace and complete the call.

In some embodiments, a control scheme may be implemented by the system800 and the switch component 812 to distribute traffic between at leasttwo platforms, one of which may be a first platform utilizes a zerocharge telephony protocol system as described herein and the other whichmay be a second platform directed to another intelligent network systemthat may or may not utilize a zero charge telephony protocol system asdescribed herein. Either or both of the platforms may utilize or notutilize the zero charge telephony protocol system. The system 800 may beconfigured to distribute traffic between at least two platforms to limitor prevent an effect on network resources and performance when switchingbetween the platforms based on time rather than primarily based on loadbalancing or partitioning associated with volume of traffic.

The system 800 may be configured to implement an alternating connectswitching scheme to distribute traffic between at least two platformsbased on a time frequency shift distribution. In an embodiment, thesystem 800 may implement CAMEL service logic that is executed at theINITDP to alternately route on a predetermined time sequence, such as oneven and odd days, between the two or more platforms. Thus, if betweenthe two platforms, the two platforms may each independently service anentire service base and volume of traffic on alternating days ratherthan partitioning the volume of traffic to assign to the two platformsto separately service concurrently. A non-limiting example of relaylogic to achieve such a scheme is set forth below:

IF Zero Balance THEN BEGIN IF even(GetDate.Day) // is current day evennumbered (MOD 2 = 0) THEN CONNECT XXXB // where XXX is the FIRSTPLATFORM route ELSE CONNECT YYYB // where YYY is the SECOND PLATFORMroute END ELSE CONTINUE

The YYY route may permit the second platform to service the base on oddnumbered days in the example above. Through such an alternating connectswitching scheme, callback CDR reconciliation for each platform may becomputed on distinctly tagged CDR sets (e.g., XXXB and YYYB).

In embodiments of the alternating connect switching scheme, the system800 may be configured to thus load balance on a time domain todistribute traffic between at least two platforms to host multipleplatforms on a single event trigger. The system 800 may further beconfigured to host multiple platforms and distribute traffictherebetween based on high frequency (e.g., switching oscillation) bycomputing, for example, even/odd day time sequences down to amicro/nanosecond or other level to be elastic and scalable. The system800 may thus make such distribution determinations beyond a binaryconsideration such as utilizing an even/odd day time sequence to adecimal or smaller time value based switching matrix determination.

Such dynamic switching may be utilized in other applications as well,such as distributing network packets over multiple links on a timesequence of a micro/nanosecond tick. For example, based on a number oflinks, such as 10 links, the system 800 may route on the lastmicro/nanosecond digit to a selected platform. Based on another numberof links, such as 100 links, the system 800 may route on the last twomicro/nanosecond digits to a selected platform. Such dynamic switchingon a time-based sequence may be applied to data paths on nano integratedcircuits as well for parallel processing.

In one embodiment, the INITDP Service Logic for Zero charge callers mayincorporate computational steps to alternate switching between aplurality of platforms (e.g., service nodes hosted by different vendors)by programmatically commanding the MSC to CONNECT the call alongdifferent routes. In one embodiment, this programmatic routing is basedon a timing parameter as shown in FIGS. 9A and 9B described below. Inanother embodiment, the programmatic routing may be based on the callerselection from a plurality of service options. In yet another embodimentdiscussed in greater detail below, the automated routing may be based ona mid call (MC) selection by a user from interactive options presentedto the user at an origination of the call.

FIG. 9A depicts automated routing based on a timing parameter via analternating connect switching scheme of low frequency that is based ontime in terms of day sequences to use with the system 800 of FIG. 8.FIG. 9A shows an embodiment of a binary alternating connect switchingscheme embodiment configured to switch traffic between two nodes, andwhich may be further configured to determine the call routing prefix asthe call path through the network as described herein based on whetherthe current day is an odd or an even numerical date. Thus, thealternating connect switching scheme of FIG. 9A presents an alternateconditional statement to that described in FIG. 6A above.

In an embodiment, when a Prepaid call is requested, the MSC/gsmSSFenters the O-BSCM. On encountering the INITDP (DP2) the MSC/gsmSSFrequests call control from a servicing gsmSCF-X (640), with SK-1, toinvoke the Prepaid Service Logic Program Instance SLPI-1, which executesthe conditional statement of the alternating connect service logic 900commanding the MSC as described below.

In flow item 901, the gsmSCF performs a credit verification for thecaller A. If the account associated with the caller A dialing an addressof user B has insufficient balance or credit to complete the call, then,in flow item 902, the program enters and begins a code block. In flowitem 903, the service logic determines whether the current day is aneven number by, for example, evaluating the expression (day modulus2=0). If that expression yields TRUE, then the current day is EVENnumbered. It is to be understood that different logical expressions maybe utilized to deliver a similar result.

The expression in flow item 903 will logically return TRUE if thecurrent day in a date object returned by a GetDate or similar functionis numerically EVEN, otherwise it returns FALSE (ODD). For example, aliteral Date may be represented in YYYYMMDD notation, where YYYY is theyear, MM is the month, and DD is the day.

The disclosed alternating connect switching method may evaluate theexpression on the full date object, as described above, by including theyear, month, and day, evaluate the expression on the numericalequivalent, or alternatively simply evaluate the expression on the daycomponent in isolation. As a non-limiting example, Aug. 18, 2020, wouldreturn TRUE as “18” is an even day number.

In flow item 904, the even numbered day results in the gsmSCF commandingthe MSC/gsmSSF to CONNECT the call on a modified address of user B,incorporating a routing prefix XXX identifying the route to a servicenode X. If the expression in flow step 903 returns FALSE, then thecurrent day is ODD numbered. In flow item 905, the odd numbered dayresults in the gsmSCF commanding the MSC/gsmSSF to CONNECT the call on amodified address of user B incorporating a routing prefix YYYidentifying the route to a service node Y. This ends the code block withan End command at flow item 906. If the caller has sufficient credit,flow item 907 executes by instructing the MSC/gsmSSF to CONTINUE thecall as dialed without modifying the B address signals.

FIG. 9B depicts another embodiment of automated routing based on atiming parameter via an alternating connect switching scheme of highfrequency that is based on time in terms of microseconds to use with thesystem 800 of FIG. 8. For higher frequency switching oscillation, thedisclosed alternating connect switching scheme may use greater precisiontiming than the day timing sequence of FIG. 9A, including withoutlimitation second based scheme down to a current millisecond (in 10⁻³seconds), a microsecond (in 10⁻⁶ second) and a nanosecond (in 10⁻⁹seconds). Describing this higher frequency alternating connect switchingin greater detail with reference to FIG. 9B, which recites theconditional statement of the alternating connect service logic 920commanding the MSC as described below.

In flow item 921, the gsmSCF performs a credit verification for thecaller A. If the account associated with the caller A dialing an addressof user B has insufficient balance or credit to complete the call, then,in flow item 922, the program enters and begins a code block. In flowitem 923, the service logic determines whether the current microsecond,for example, is an even number, by evaluating an expression (microsecondmodulus 2=0). If that expression yields TRUE, the current microsecond isEVEN numbered. It is to be understood that different logical expressionsmay be utilized to deliver a similar result.

The expression in flow item 923 may return TRUE if the currentmicrosecond in a datetime object returned by a GetDateTime or similarfunction is numerically EVEN, otherwise it returns FALSE (ODD). Forexample, a DateTime object may be represented in the following format:YYYYMMDDHHMMSSMMSSSNNN, where YYYY is the year, MM is the month, DD isthe day, HH is the hour, MM is the minute, SS is the second, MMM are themilliseconds, SSS are the microseconds, and NNN are the nanoseconds. Asa non-limiting example, 20200818103019601230111 modulus 2 would returnFALSE as it is an odd number. Similarly, the microseconds in the above,230 modulus 2, would return TRUE as it is an even number. The disclosedalternating connect switching scheme of FIG. 9B may evaluate theexpression on the full datetime object, down to the required precisionpoint, such as down to the microsecond, either by including the date andpreceding time components, or on the numerical equivalent.Alternatively, the expression may simply evaluate using just themicrosecond component alone.

In flow item 924, the even numbered microsecond results in the gsmSCFcommanding the MSC/gsmSSF to CONNECT the call on a modified address ofuser B, incorporating a routing prefix XXX identifying the route to aservice node X. If the expression in flow item 923 returns FALSE, thenthe current microsecond is ODD numbered. In flow item 925, the oddnumbered day results in the gsmSCF commanding the MSC/gsmSSF to CONNECTthe call on a modified address of user B incorporating a routing prefixYYY identifying the route to a service node Y. This ends the code blockwith an End command at flow item 926. If the caller has sufficientcredit, flow item 927 executes by instructing the MSC/gsmSSF to CONTINUEthe call as dialed without modifying the B address signals.

In one embodiment automatic routing on a time factor T (e.g., where Tmay be without limitation, the current day, current hour, currentmillisecond, current microsecond, current nanosecond, or other suitabletime feature) amongst N network service nodes, where each node has arouting prefix P, stored in an array A, with starting index zero, may becomputed via an expression P=A [T mod N]. This expression is configuredto distribute traffic amongst, for example, three nodes on nanosecondtime as follows. For example, traffic is distributed to the 1st nodeA[0] on nanosecond=0, 3, 6, 9 . . . (modulus 3=0), to the 2nd node A[1]on nanosecond=1, 4, 7, 10 . . . (modulus 3=1), and to the 3rd node A[2]on nanosecond=2, 5, 8, 11 . . . (modulus 3=2).

In yet another embodiment, the automated routing of the system 800 viathe switching component 812 may be based on a mid-call (MC) selection bya user from interactive options presented to the user at an originationof the call. In some embodiments, the time driven alternating connectscheme may be applied concurrently with the user-selection-drivenalternating connect scheme, which is described in greater detail below.User selection of a service option may utilize a time based alternatingswitching scheme of FIG. 9A or 9B to split across multiple serviceplatforms associated with the service option. For example, selection offinancial services as a service option may cause the alternating connectswitching mechanism to further use the low frequency time-based optionof FIG. 9A or the high frequency time based option of FIG. 9B to equallyor in other portions divide traffic across multiple Fintech platforms.

In an MC embodiment based on such a user-selection-driven alternatingconnect scheme employing an MC selection, the alternating connectservice switching logic may be driven by caller service selection inresponse to the gsmSCF utilizing a gsmSRF (Specialized ResourceFunction) to relay a service announcement, such as “Press Star forServices”, or present a menu with a plurality of service options to thecaller. Such a mid-call menu may be presented prior to conducting thecredit verification at flow item 901, to provide systemic operatorspecific services (OSS) to callers. Alternatively the mid-call menu maybe presented on determining the caller has insufficient credit tocomplete the call, at flow item 901, within the service block beginningat flow item 902. In the latter embodiment, OSS may be tailored to lowor zero balance callers.

The gsmSRF thus enables inband caller interaction with the IntelligentNetwork to control early call setup, service selection, routing andredirection orchestrated by the gsmSCF, which instructs the gsmSRF toplay announcements and collect digits or voice commands for serviceselection. Interleaving this advanced mid-call service logic asdescribed during the INITDP phase of the call seamlessly injects OSSinto the mass dial stream.

Such a user selected and user driven call control procedure may thenpermit the gsmSCF to determine which routing prefix to apply to thecall, in order to CONNECT on a modified B address incorporating thedetermined routing prefix, and thereby reroute the call to the attendantservice platform. As a non-limiting example, after announcing to a lowor zero balance caller to “Press Star for Advanced Credit,” and uponreceiving a star DTMF signal from the handset of the caller, the gsmSCFmay command the MSC/gsmSSF to connect the call to XXXB, where XXX is therouting prefix for an Advanced Credit Control Platform.

FIG. 10 depicts in greater detail an embodiment of mid-call user drivenCONNECT switching. In flow item 1000, prepaid user A dials user B.Prepaid user is recited as a non-limiting example. On receiving the callsetup request, the MSC/gsmSSF may enter the O-BSCM. On encountering theINITDP (DP2) the MSC/gsmSSF may request call control from servicinggsmSCF-X (640), with SK-1. This may invoke the Prepaid Service LogicProgram Instance SLPI-1, which in this embodiment incorporatesadditional service logic as depicted in FIG. 9A, which in thisembodiment may be further modified as follows:

In flow item 1001, the gsmSCF performs a credit verification for thecaller A. By way of non-limiting example, if the account associated withthe caller A dialing an address of user B has insufficient balance orcredit to complete the call then in flow item 1002 the gsmSCF instructsthe gsmSRF to announce service options (for example, service option X orY) to the caller and to collect any digits or voice commands as theselection response.

In flow item 1003 the gsmSCF awaits said caller selection. If the callerhas sufficient credit to complete the call, the gsmSCF in flow item 1012commands the MSC/gsmSSF to CONTINUE with the call toward the Bdestination in flow 1013. In flow item 1004, absent any selection inputfrom the caller within a specified time, the gsmSCF may select a defaultrouting prefix ZZZ for the call and in flow item 1014 the gsmSCFcommands the MSC/gsmSSF to CONNECT the call on the now modified Baddress signals incorporating the default routing prefix, as in ZZZB.

In flow item 1005, if the gsmSCF receives caller selection input withinthe specified selection timeout window, and the service selection optionis X, then in flow item 1006 the gsmSCF may modify the B address signalsto incorporate the XXX routing prefix associated with the X serviceselection, and may command the MSC/gsmSSF to CONNECT the call todestination XXXB.

In flow item 1015, if the gsmSCF receives caller selection input withinthe specified selection timeout window, and the service selection optionis Y, then in flow item 1016 the gsmSCF may modify the B address signalsto incorporate the YYY routing prefix associated with the Y serviceselection, and may command the MSC/gsmSSF to CONNECT the call todestination YYYB.

On receiving the CONNECT command with the modified B address, theMSC/gsmSSF may perform a routing lookup on the specified prefix (e.g.XXX, YYY or ZZZ) and routes the call along the designated trunk to theassociated service platform. In one mid-call service non-limitingexample, callers are permitted to make limited duration free calls inreturn for example, listening to short third party advertisements,undertaking a public poll or listening to public service announcementsin some embodiments. For example, a MVNO (Mobile Virtual NetworkOperator) purchases wholesale airtime from the host carrier whoannounces the free call service mid-call per the disclosed methods. TheMVNO sells advertising to third parties, or conducts public polls, whichit plays to captive callers who in return are permitted to enjoy limitedduration free calls. This free call service is described in theembodiment described below in more detail with reference to FIG. 11.

In FIG. 11, flow item 1100 Prepaid user A dials user B. Prepaid is usedas a non-limiting example. Upon receiving the requested call, theMSC/gsmSSF may enter the O-BSCM. Upon encountering the INITDP (DP2) theMSC/gsmSSF requests call control from servicing gsmSCF-X (640), withSK-1 in flow 1101. This may invoke the Prepaid Service Logic ProgramInstance SLPI-1, which executes the following disclosed Service Logic:

In flow item 1102 the gsmSCF instructs the gsmSRF to play anannouncement to the caller, for example, “Press * for Free Call” and inflow 1103 awaits input from the caller collected by the gsmSRF. Thisinput may be collected via DTMF, voice command, and the like. If no star(or other appropriate input) selection is made by the caller, then thegsmSCF in flow item 1114 may perform a credit verification and servicethe call per FIGS. 1A and 2 above, for example.

In flow item 1104, if the * key selection was received, then the gsmSCFin flow 1105 may command the MSC/gsmSSF to CONNECT the call on amodified B address incorporating the XXX routing prefix for, by way ofnon-limiting example, the MVNO advertisement sponsored telephonyplatform. Upon receiving the CONNECT command with the modified Baddress, the MSC/gsmSSF may perform digit analysis and a routing lookupon the specified XXX prefix and route the call along the designatedtrunk to the associated MVNO service platform. By way of non-limitingexample, in an Internet Cloud hosted MVNO embodiment, this call requestis routed via the host carrier GMSC/SBC, which may be utilized totranslate ISUP into SIP signaling as disclosed earlier.

In flow item 1106 the MVNO platform may answer the call (going OFF HOOK)and play an audio advertisement to the captive caller. This audiosession may be interactive, soliciting further input from the caller. Inone embodiment, this advertisement may be targeted to the caller usingthe A party MSISDN obtained in the call setup request. Continuing withthis embodiment, the MVNO, in addition to playing the audioadvertisement, may also send an internet link to the A party, such asfor posterity and/or later review. Such a linked reference may include,by way of non-limiting example, special offers from the advertiser tothe caller.

In flow item 1107, after advertisement playback completion, the MVNO maythen proceed to continue the original call request by connecting, forexample, the A and the B party. In one embodiment the MVNO platform mayestablish a second call leg to the B party, with the A party Caller LineIdentity, then bridging the A and B party calls. In one such free callembodiment, the MVNO offers a limited duration call, for example a oneminute or five minute call (by way of non-limiting example) dependent onthe revenue the MVNO receives from the advertiser. Optionally, at maxcall duration minus T seconds, the MVNO may play an in-call advancewarning tone, signaling that the call is about to terminate. Uponreaching the maximum call duration permitted for the call, the MVNOdisconnects the call. In one embodiment the MVNO may present additionaladvertisements to both A and B parties, on the connected call, andthereafter permit the call to continue for another predeterminedduration. Upon call termination the completed call may generate an XXXBtagged CDR on the host carrier Originating MSC, which may then beaudited to compute the Minutes of Use for the MVNO which is typicallysettled at wholesale rates. While this embodiment describes an MVNOproviding the free advertisement sponsored call, the host carrier mayitself provide such a service directly, utilizing the disclosed INITDPintelligent control service logic.

In one embodiment, the free advert sponsored telephony service isautomatically engaged upon determining that the caller has insufficientcredit to complete the call. For example, without playing anannouncement and awaiting user selection, upon determining that thecaller has insufficient credit, the gsmSCF commands the MSC/gsmSSF toCONNECT the call on the modified B address incorporating the XXX routingprefix as disclosed.

The alternating connect switching schemes described herein may be basedon a parameter of time, user selection, AI, or combinations thereof toeffect switching between two or more platforms to service a call andadvance the call to a final destination. In one embodiment the platformmay be utilized to transact between the A and B party addresses capturedin the call request. For example, on selecting an appropriate mid calloption, the servicing platform may permit the caller A to transferairtime or currency, either through menu selection or via direct inputusing DTMF signals, to party B without completing the call to the Bdestination device, the mid-call platform thereby delivering what may betermed peer-to-peer ring free services. The final destination thus maybe to the called party B (e.g., to the second user mobile device 308,338 of user B) or another destination such as a service vendor. Invarious embodiments, the service vendor may be a mid-destination, suchas based on a user selection, prior to arriving at a final destinationsuch as the called party B. When based on the parameter of userselection, IVR may be utilized at origination to present options to acalling party A (at the first user mobile device 300, 330 of user A)that may suspend the call and redirect the call based on the selectedoption along an associated platform as the selected service node. Thus,a service control point is configured to interleave and connect operatorspecific services. Such services may be presented to callers in the dialstream at origination such that the call may directly control theIntelligent Network determination on how to automatically route the calland along which selected platform of multiple platform options. Thesystem 800 may be configured to present an originating MC operatorspecific service selection from a plurality of service options and/orannouncements. The system may further be configured to relay informationor announcements to the calling party user, e.g., advertisements, publicservice announcements, interactive polls, etc.

In such an MC embodiment relaying such information, in a wholesale MVNOmodel, an entity X may purchase minutes from a host carrier and presentan option of “Press [code] to connect your call FREE” on the carrierservice in response to a call. The code may be, for example, a starsymbol * or another code. When a user initiates the call, the user A, asthe calling party, may be presented with the option and press the codeto proceed with a free call. The gsmSCF may then issue a connect commandto connect the call to XXXB. The system may then relay selected orpre-determined information, or a sponsor, e.g., company X, may then bepermitted through the system 800 to relay information, to the captiveuser A, and then user A might be connected to user B without charge orat a reduced fee. The sponsor may then settle minutes of use associatedwith the call or calls, e.g., at a wholesale rate, with the carrier. Thesystem 800 is configured to permit a virtual provider platform to hookdirectly into a mass dial-stream to offer at scale a viable andsponsored telecommunications platform that is available to the user at areduced rate or fee, but yet is still commercially appealing to thecarrier.

Such MC embodiments may provide a wide variety of goods and serviceoptions as are generally commercially advertised through other media,including, but not limited to, Fintech, insurance, transaction services,and the like. By way of example, and not as a limitation, a call fromuser A to user B may be levered to connect to a service option totransfer funds. User A may call user B as described herein. In oneembodiment, before or after determining whether a User A has sufficientcredit for the call, a service option may be presented mid-call atorigination of the call. In another embodiment, in which a determinationregarding sufficiency of credit is not made with respect to the call,the service option may still be presented mid-call at origination of thecall. The service option may be an option to transfer airtime such asthrough selection of a code associated with the service option, whichmay be, for example, *1. Upon selection of the code associated with theservice option, the user A may be directed to implement steps totransfer an input amount, such as $10, to user B. The call maydisconnect at this point. In other embodiments, another service optionmay be presented to continue to advance the call to user B or the callmay be configured to automatically continue to call to user B asdescribed herein.

The alternating connect switching schemes based on a parameter of time,user selection, AI, or combinations thereof may cause the system 800 toswitch at a service control point (SCP) between at least two platformsto service the call and advance the call to a final destination. Thefinal destination may be an end destination associated with theswitched-to platform, the second user mobile device 308, 338 of user Bas the called party, or another destination.

It is noted that recitations herein of a component of the presentdisclosure being “configured” or “programmed” in a particular way, toembody a particular property, or to function in a particular manner, arestructural recitations, as opposed to recitations of intended use. Morespecifically, the references herein to the manner in which a componentis “configured” or “programmed” denotes an existing physical conditionof the component and, as such, is to be taken as a definite recitationof the structural characteristics of the component.

It is noted that the terms “substantially” and “about” may be utilizedherein to represent the inherent degree of uncertainty that may beattributed to any quantitative comparison, value, measurement, or otherrepresentation. These terms are also utilized herein to represent thedegree by which a quantitative representation may vary from a statedreference without resulting in a change in the basic function of thesubject matter at issue.

While particular embodiments have been illustrated and described herein,it should be understood that various other changes and modifications maybe made without departing from the spirit and scope of the claimedsubject matter. Moreover, although various aspects of the claimedsubject matter have been described herein, such aspects need not beutilized in combination. It is therefore intended that the appendedclaims cover all such changes and modifications that are within thescope of the claimed subject matter.

1. A zero charge telephony protocol system comprising: one or moreprocessors; a non-transitory memory communicatively coupled to the oneor more processors; and machine readable instructions stored in thenon-transitory memory that cause the system to perform at least thefollowing when executed by the one or more processors: receive, from afirst user mobile device associated with a first user account, a callsignal comprising a request to place and complete a call to a mobileaddress of a second user mobile device; automatically modify the mobileaddress with a routing prefix to generate a modified call signalcomprising a modified address, including the routing prefix, when thefirst user account has insufficient balance to complete the call or isindependent of balance; route to an asynchronous signaling switch basedon a trunk communication path associated with the modified address;revert the modified call signal at the asynchronous signaling switch tothe call signal; deliver the call signal from the asynchronous signalingswitch to the second user mobile device to complete the call; andautomatically disconnect the call from the second user mobile deviceimmediately upon receipt of the call signal by the second user mobiledevice.
 2. The zero charge telephony protocol system of claim 1, furthercomprising machine readable instructions that cause the system toperform at least the following when executed by the one or moreprocessors: receive from the first user mobile device the request at aMobile Switching Center (MSC) to place and complete the call to themobile address of the second user mobile device; lookup a pre-configuredrouting table including a trunk indicator of the trunk communicationpath associated with the modified address; route the modified addressbased on the trunk indicator of the trunk communication path associatedwith the modified address from the pre-configured routing table;automatically route the modified call signal along the trunkcommunication path from the MSC to a Gateway MSC (GMSC); andautomatically route the modified call signal along the trunkcommunication path from the GMSC to the asynchronous signaling switch.3. The zero charge telephony protocol system of claim 1, wherein themachine readable instructions further cause the system to perform atleast the following when executed by the one or more processors:disconnect the call from the first user mobile device by theasynchronous signaling switch when the first user account hasinsufficient balance to complete the call in concurrence to routing thecall signal to the second user mobile device; track the call between thefirst user mobile device, the asynchronous signaling switch, and thesecond user mobile device with a plurality of call data recording codesassociated with the call within a period of time; and charge a seconduser account of the second user mobile device based on the plurality ofcall data recording codes associated with the call upon a callback fromthe second user mobile device to the first user mobile device within theperiod of time.
 4. The system of claim 1, wherein the machine readableinstructions further cause the system to perform at least the followingwhen executed by the one or more processors: deliver the call signalfrom the asynchronous signaling switch to the second user mobile devicealong with an identification delivery configured to identify the firstuser mobile device, a ringing permission, and an answering restriction;and automatically disconnect the call from the second user mobile devicebased on receipt by the second user mobile device of the identificationdelivery, the ringing permission, and the answering restriction.
 5. Thesystem of claim 4, wherein the machine readable instructions furthercause the system to perform at least the following when executed by theone or more processors: automatically modify the mobile address with therouting prefix including a star symbol to generate the modified callsignal comprising the modified address including the star symbol as therouting prefix when the first user account has insufficient balance tocomplete the call.
 6. The zero charge telephony protocol system of claim1, wherein: the first user account is associated with abalance-dependent subscriber identification module (SIM) card and abalance-independent SIM card; the balance-dependent SIM card isconfigured to include balance to place and complete the call and incur acharge through a balance-dependent service key invoking abalance-dependent logic when the first user account has sufficientbalance to complete the call; and the balance-independent SIM card isconfigured to place and complete the call without charge through abalance-independent service key invoking a no-charge logic separate fromthe balance-dependent logic when the first user account has insufficientbalance to complete the call.
 7. The zero charge telephony protocolsystem of claim 1, wherein the first user account is associated with abalance-independent SIM card such that the first user account isconfigured to place and complete the call via the balance-independentSIM card independent of balance.
 8. The system of claim 7, wherein themachine readable instructions further cause the system to perform atleast the following when executed by the one or more processors: receivea payment in the first user account; and modify the balance-independentSIM card into a balance-dependent SIM card having a positive balancesufficient to place and complete a call.
 9. A method of implementing azero charge telephony protocol, the method comprising: receiving, from afirst user mobile device associated with a first user account, a callsignal comprising a request to place and complete a call to a mobileaddress of a second user mobile device; automatically modifying themobile address with a routing prefix to generate a modified call signalcomprising a modified address including the routing prefix when thefirst user account has insufficient balance to complete the call or isindependent of balance; routing to an asynchronous signaling switchbased on a trunk communication path associated with the modifiedaddress; reverting the modified call signal at the asynchronoussignaling switch to the call signal; delivering the call signal from theasynchronous signaling switch to the second user mobile device tocomplete the call; and automatically disconnecting the call from thesecond user mobile device immediately upon receipt of the call signal bythe second user mobile device.
 10. The method of claim 9, furthercomprising: receiving from the first user mobile device the request at aMobile Switching Center (MSC) to place and complete the call to themobile address of the second user mobile device; looking-up apre-configured routing table including a trunk indicator of the trunkcommunication path associated with the modified address; routing themodified address based on the trunk indicator of the trunk communicationpath associated with the modified address from the pre-configuredrouting table; automatically routing the modified call signal along thetrunk communication path from the MSC to a Gateway MSC (GMSC); andautomatically routing the modified call signal along the trunkcommunication path from the GMSC to the asynchronous signaling switch.11. The method of claim 9, further comprising: disconnecting the callfrom the first user mobile device by the asynchronous signaling switchwhen the first user account has an insufficient balance to complete thecall in concurrence to routing the call signal to the second user mobiledevice; tracking the call between the first user mobile device, theasynchronous signaling switch, and the second user mobile device with aplurality of call data recording codes associated with the call within aperiod of time; and charging a second user account of the second usermobile device based on the plurality of call data recording codesassociated with the call upon a callback from the second user mobiledevice to the first user mobile device within the period of time. 12.The method of claim 9, further comprising: delivering the call signalfrom the asynchronous signaling switch to the second user mobile devicealong with an identification delivery configured to identify the firstuser mobile device, a ringing permission, and an answering restriction;and automatically disconnecting the call from the second user mobiledevice based on receipt by the second user mobile device of theidentification delivery, the ringing permission, and the answeringrestriction.
 13. The method of claim 12, further comprising:automatically modifying the mobile address with the routing prefixincluding a star symbol to generate the modified call signal comprisingthe modified address including the star symbol as the routing prefixwhen the first user account has insufficient balance to complete thecall.
 14. The method of claim 9, wherein: the first user account isassociated with a balance-dependent subscriber identification module(SIM) card and a balance-independent SIM card; the balance-dependent SIMcard is configured to include balance to place and complete the call andincur a charge through a balance-dependent service key invoking abalance-dependent logic when the first user account has sufficientbalance to complete the call; and the balance-independent SIM card isconfigured to place and complete the call without charge through abalance-independent service key invoking a no-charge logic separate fromthe balance-dependent logic when the first user account has insufficientbalance to complete the call.
 15. The method of claim 9, wherein thefirst user account is associated with a balance-independent SIM cardsuch that the first user account is configured to place and complete thecall via the balance-independent SIM card independent of balance. 16.The method of claim 15, further comprising: receive a payment in thefirst user account; and modify the balance-independent SIM card into abalance-dependent SIM card having a positive balance sufficient to placeand complete a call.
 17. A zero charge telephony protocol systemcomprising: one or more processors; a non-transitory memorycommunicatively coupled to the one or more processors; and machinereadable instructions stored in the non-transitory memory that cause thesystem to perform at least the following when executed by the one ormore processors: receive, from a first user mobile device associatedwith a first user account, a call signal comprising a request to placeand complete a call to a mobile address of a second user mobile device;automatically set a call duration time quota upon a synchronous chargingonset when the first user account has insufficient balance to completethe call; deliver the call signal to the second user mobile device tocomplete the call; and automatically disconnect the call from the seconduser mobile device when the call duration time quota is exceeded afterthe synchronous charging onset.
 18. The zero charge telephony protocolsystem of claim 17, further comprising machine readable instructionsthat cause the system to perform at least the following when executed bythe one or more processors: continue to place the call when the firstuser account has sufficient balance to complete the call; and permit thecall to proceed to speech post answering by the second user mobiledevice and based on the sufficient balance.
 19. The zero chargetelephony protocol system of claim 17, wherein the first user account isassociated with a balance-dependent subscriber identification module(SIM) card configured to include a balance to place and complete thecall.
 20. The zero charge telephony protocol system of claim 17, whereinthe call duration time quota is 0 to 1 second from the synchronouscharging onset.